Title: Searching for Ecoterrorism
Subtitle: The Crucial Case of the Unabomber
Author: Sean Fleming
Date: 6 February 2024
Notes: Sean Fleming, University of Nottingham. sean.fleming@nottingham.ac.uk
Publisher: Cambridge University Press
Copyright notice: © The Author(s), 2024. Published by Cambridge University Press on behalf of American Political Science Association. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.


A key finding of recent scholarship on political violence is that environmentalists rarely, if ever, use lethal violence. Many scholars have argued that “ecoterrorism” is a misnomer for what is more accurately termed “ecotage.” Large-n studies of environmental activism have identified only one apparent example of an environmentally motivated terrorist: the Unabomber, Ted Kaczynski. The Unabomber case is therefore a “crucial case” for evaluating the Peaceful Environmentalist Thesis—the generalization that environmentalists do not use lethal violence. Pioneering a forensic method of ideology analysis, this article uses previously unexamined archival material to assess the Unabomber’s affinities with three environmental ideologies: radical environmentalism, green anarchism, and right-wing ecologism. It shows that the Unabomber’s ideology is not environmentalist in intellectual origins or in conceptual structure, and that his motivations were anti-technological rather than pro-ecological. The Unabomber case demonstrates how ideology analysis can complement and strengthen research on political violence.


A key finding of recent scholarship on political violence is that environmentalists rarely, if ever, use lethal violence. Although cases of environmentally motivated sabotage are common, cases of environmentally motivated murder are difficult to find (Carson, LaFree, and Dugan 2012; Hirsch-Hoefler and Mudde 2014; Loadenthal 2017; Taylor 1998; 2003). Many scholars have therefore argued that “ecoterrorism” is a misnomer for what is more accurately termed “ecotage” (Amster 2006; Cooke 2013; Loadenthal 2014; Smith 2008; Sumner and Weidman 2013; Vanderheiden 2005; Wagner 2008; Woodhouse 2014). According to the expansive definitions of terrorism used by many law enforcement agencies, which encompass any “unlawful use of force or violence against persons or property” for “social or political objectives” (Pomerantz 1987, 14–5), environmentally motivated sabotage is terrorism. However, critics insist on a distinction between violence against property and violence against people. “There is a fundamental difference,” Sumner and Weidman (2013, 868) argue, “between destroying SUVs and flying an airplane full of people into a building full of people.” In their view, destroying SUVs is not terrorism, any more than stealing SUVs is kidnapping.

Yet, the debate about ecoterrorism is about much more than terminology. The absence of lethal attacks by environmental activists is striking, no matter how terrorism is defined. Even if politically motivated sabotage does constitute terrorism, it is nonetheless remarkable that environmental activists have limited themselves to “terrorism” against property. The generalization that environmentalists do not use lethal violence—call this the Peaceful Environmentalist Thesis—looks to be one of the strongest generalizations that contemporary political science has to offer. Unlike the Democratic Peace Thesis, which is notoriously riddled with qualifications and conditions of applicability, the Peaceful Environmentalist Thesis can be stated with powerful simplicity: environmental activists do not kill people.

There are only a few alleged counterexamples to this generalization. In his landmark study of 11,562 illegal incidents associated with the environmental and animal rights movements from 1973 through 2010, Loadenthal (2017) found only four fatal attacks. One was the 2002 assassination of the Dutch populist politician Pim Fortuyn by an animal rights activist named Volkert van der Graaf. This attack is a doubtful counterexample to the Peaceful Environmentalist Thesis for two reasons. First, although there are overlaps between the animal rights and environmental movements, it is a mistake to conflate them. Carson, LaFree, and Dugan (2012, 307) have found that “compared to environmental extremists, radical animal rights groups are more than five times more likely to target people.” They identified three cases of assassination carried out by animal rights activists but none by environmental activists (see also Taylor 2003, 180; 2004, 244–6). Second, Fortuyn’s assassin was apparently motivated by neither animal rights nor environmentalism. Van der Graaf claims to have killed Fortuyn to protect Muslims from political persecution (Evans-Pritchard and Clements 2003; Taylor 2003, 177).

The other three fatal attacks in Loadenthal’s (2017) dataset were all perpetrated by Ted Kaczynski, the American domestic terrorist known as “the Unabomber.” From 1978 through 1995, Kaczynski waged a bombing campaign in the name of “wild nature,” which killed three people and injured 23 others. Yet, his relationship with environmentalism is disputed. While some see him as a paradigmatic ecoterrorist (Arnold 1997; Barnett 2015), others argue that his claim to be fighting for nature was insincere and purely rhetorical (Chase 2004; Sale 1995).

As one of the very few plausible cases of environmentally motivated terrorism, the Unabomber case is a “crucial case” for the Peaceful Environmentalist Thesis (Eckstein 1975; George and Bennett 2005; Gerring 2007).[1] If the Unabomber is an environmentalist, then he is an important counterexample to the generalization that environmentalists do not use lethal violence—a counterexample that calls for an explanation. If he is not an environmentalist, then the Peaceful Environmentalist Thesis is even stronger than previous research suggests, because the prime counterexample turns out to be illusory. Of course, a generalization cannot be proved or disproved by a single case. But when a generalization has few apparent counterexamples, a single case can make an unusually large difference to the generalization’s strength. The Unabomber case is thus “crucial” for determining how strong the Peaceful Environmentalist Thesis is. While a generalization with one exception is very strong, a generalization with no exceptions is the holy grail of social science.

The Unabomber is important not only as a test case for theories about ecoterrorism, but also, more broadly, as an influential figure in contemporary radical politics. His 35,000-word manifesto, “Industrial Society and Its Future,” was jointly published by The Washington Post and The New York Times in September 1995 (Kaczynski 1995a). It has been translated into more than a dozen languages and is a source of ideas and inspiration for radicals across the spectrum, from anarchists to neo-fascists (Fleming 2022; Hughes, Jones, and Amarasingam 2022; Lubrano 2023). However, there is little scholarly literature about Kaczynski’s ideology (Corey 2000; Luke 1996; Moen 2019; Taylor 1998), and none of the existing literature has made use of the available archival material.

The purpose of this article is to assess Kaczynski’s relationship with environmentalism. I adopt a dual approach to ideology analysis, which combines what Freeden (1996, 3) calls “morphological” analysis of the conceptual structures of ideologies with “genetic” analysis of their intellectual origins. I rely on previously unexamined archival material from the Joseph A. Labadie Collection at the University of Michigan and the UNABOM Collection at Pennsylvania Western University. My analysis shows that Kaczynski’s ideology is not environmentalist in origin or in structure. Although it does have some affinities with radical environmentalism, green anarchism, and right-wing ecologism, it does not fit in any of these categories. Nor is Kaczynski’s ideology an idiosyncratic sort of environmentalism that belongs in a category of its own. Almost none of his ideas are from environmentalist sources, and his motivations were decidedly anti-technological rather than pro-ecological. However, the Peaceful Environmentalist Thesis does not emerge unscathed. Although Kaczynski himself is not a credible counterexample, he points to other plausible counterexamples.

The article has five main sections. The first section explains my approach and method and describes the archival evidence I use. The second section examines the common claim that Kaczynski was not, in fact, motivated by the ideas he espoused in his manifesto. This claim, if true, would provide a shortcut to my conclusion that his violence was not environmentally motivated, but it does not stand up to the evidence. The next three sections assess Kaczynski’s alleged affinities with three environmental ideologies: radical environmentalism, green anarchism, and right-wing ecologism. The conclusion reassesses the Peaceful Environmentalist Thesis in light of the Unabomber case and draws some broader implications for the study of political ideologies and political violence.

Forensic Ideology Analysis

Large-n, incident-based studies are useful for discerning patterns and “waves” of terrorist activity, and for identifying strategic and tactical differences between terrorists of different ideological types (e.g., Jaśko et al. 2022; Piazza 2009). That environmentalists seldom, if ever, use lethal violence is one of the key findings of this kind of research (Carson, LaFree, and Dugan 2012; Loadenthal 2017). However, an important weakness of large-n, incident-based studies is that they tend to rely on impressionistic categorizations of terrorists’ ideologies. When coding attacks or “incidents,” scholars must often make heuristic judgments about the perpetrators’ ideologies, because many incidents have not been studied at any depth.

Although it has long been recognized that terrorists’ ideologies shape their patterns of target selection and determine the lethality of their attacks (Ahmed 2018; Asal and Rethemeyer 2008; Drake 1998), terrorism scholars have only recently begun to develop rigorous approaches to ideology analysis (Ackerman and Burnham 2021; Holbrook and Horgan 2019). They have so far made little use of the well-established approaches to ideology analysis in political theory (Freeden 1996; Leader Maynard 2013; Ostrowski 2022). These approaches can not only add depth to small-n studies of terrorism; they can also aid large-n studies by helping scholars categorize and code terrorists’ ideologies in a more systematic way.

I adopt a dual approach to the study of ideology, which combines what Freeden (1996, 3) calls “morphological” and “genetic” analysis. An ideology can be analyzed morphologically, based on the configuration of concepts that it employs, or genetically, based on its intellectual lineage. This dual approach captures two ways in which claims of ideological identity are commonly intended and understood. The claim that the Unabomber was an environmentalist may mean that his ideology displays a conceptual structure that is characteristic of environmentalism (morphological), that it belongs to the intellectual tradition of environmentalism (genetic), or both.

To guard against definitional gerrymandering, I begin with a working definition of environmentalism that errs on the side of over-inclusiveness: environmentalism is a family of ideologies that are centrally concerned with ecology or nonhuman nature. This definition encompasses anthropocentric varieties of environmentalism, which are concerned with the preservation of “natural resources” for the benefit of human beings, as well as ecocentric varieties of environmentalism that ascribe intrinsic value to nonhuman nature. The qualifier, “nonhuman,” is implied by the etymology of “environment,” which means “something that surrounds”—something external to humanity (Winner 2020, 123). This qualifier is necessary to distinguish anthropocentric varieties of environmentalism from ideologies that are primarily concerned with the preservation of human nature. For example, groups such as Ducks Unlimited, which advocate wildlife conservation for the purpose of hunting, can plausibly be counted as environmentalist groups. However, groups that oppose genetic engineering or “human enhancement” on moral or religious grounds are not necessarily environmentalist groups, even though they are, in a sense, concerned with the preservation of nature. As a rough heuristic, then, an ideology can provisionally be considered “environmentalist” if it is centrally concerned with ecology or nonhuman nature. Yet, morphological and genetic analyses are necessary to adjudicate ambiguous cases, such as that of the Unabomber. Instead of simply assessing whether Kaczynski’s ideology fits an arbitrary (and inevitably contested) definition of environmentalism, it is more fruitful to compare his ideology to ideologies that are widely recognized as environmentalist, both by their own proponents and by others.

My assessment of Kaczynski’s relationship with environmentalism is based on both morphological and genetic criteria: (1) the strength/weakness of the conceptual similarities between his ideology and the environmental ideologies with which it has been equated (i.e., radical environmentalism, green anarchism, and right-wing ecologism); and (2) the strength/weakness of Kaczynski’s intellectual-historical connections to the environmentalist tradition (i.e., whether his ideas are drawn from environmentalist sources). There are four possibilities. If Kaczynski’s relationship with environmentalism is both morphologically and genetically strong, then he is an unambiguous counterexample to the Peaceful Environmentalist Thesis. If his relationship with environmentalism is weak according to both criteria, then he can be excluded from the category of environmentalists altogether. If his ideology displays strong morphological similarities to environmental ideologies but weak intellectual-historical links, then he might be considered an idiosyncratic or sui generis sort of environmentalist, but nonetheless a fairly strong counterexample to the Peaceful Environmentalist Thesis. Finally, if his ideology displays weak morphological similarities to environmental ideologies but strong intellectual-historical links, then it might be considered a cousin of environmentalism—a relatively weak counterexample.

While my interpretative approach combines morphological and genetic ideology analysis, my method is “forensic.” So far, claims about Kaczynski’s ideology have been based on highly circumstantial evidence, such as terminological similarities and biographical information. Much like a detective would, I put these claims to the test using hard, physical evidence. Blau (2015) has argued that “detective-work” is a helpful analogy for the study of ideas. I take “detective-work” literally and examine Kaczynski’s ideology using the same body of evidence that the FBI used. The University of Michigan’s Labadie Collection contains copies of much of the material that the FBI confiscated from his cabin in 1996, including his journals, notes, drafts, and unpublished essays. It also contains copies of his prison correspondence from 1996 to the late 2010s.[2] Pennsylvania Western University’s UNABOM Collection contains additional letters and other writings by Kaczynski, which were donated by James R. Fitzgerald, a forensic linguist and former FBI agent who played a pivotal role in the Unabomber case. None of the existing literature about Kaczynski’s ideas makes use of these rich archives (Chase 2004; Corey 2000; Luke 1996; Sale 1995; Staudenmaier 2021; Taylor 1998). Early analyses of the Unabomber manifesto were unavoidably speculative, because the forensic evidence was not yet available. The Labadie Collection’s Kaczynski Papers did not open to the public until 2000, and the UNABOM Collection was not available until 2021. In the next four sections, I test the common claims about Kaczynski’s relationship with environmentalism against this body of forensic evidence, using the dual morphological-genetic approach to guide my interpretations.

Insanity and Insincerity

The claim that Kaczynski was an ecoterrorist assumes that he was, in fact, motivated by ideas. Two opposing narratives emerged after Kaczynski’s arrest, both of which raise doubts about whether his violence was politically motivated. On one side, against his vehement objections, Kaczynski’s lawyers argued that his bombing campaign was the product of serious mental illness. A psychiatrist for the defense gave Kaczynski a provisional diagnosis of schizophrenia and said that his beliefs about technology were manifestations of pathological paranoia (Johnson 1998). If this is true, then Kaczynski’s system of beliefs was not really a political ideology, but a collection of idiosyncratic delusions. On the other side, the prosecutors portrayed Kaczynski as a cold, calculating murderer. He was neither a paranoid schizophrenic nor an idealistic radical, they argued, but a sadistic serial killer (Seave 1998). The defense and the prosecution implicitly agreed that Kaczynski’s bombing campaign was to be explained by his psychology, not his ideology. Since terrorism is, at a minimum, politically motivated violence, on neither account can Kaczynski be considered a terrorist, let alone an ecoterrorist.

There is little doubt that Kaczynski suffered from mental illness. He sought help for depression, anxiety, and insomnia from Montana Mental Health Services on multiple occasions between 1988 and 1993 (UNABOM Task Force 1996, 155–7, 209–19). However, there is little evidence that Kaczynski experienced psychosis or delusions. According to legal scholar Michael Mello (2000, 448), the foremost expert on the Unabomber case, “the evidence that Theodore Kaczynski suffers from paranoid schizophrenia, or any other actual, serious mental illness, is surprisingly flimsy—unless anti-technology politics, a willingness to kill for them, and a reclusive lifestyle all add up to mental illness.” After extensively corresponding with him, Mello (2000, 472–3) concluded that Kaczynski “wasn’t a mad bomber; he was a chillingly sane bomber.” James Q. Wilson, former president of the American Political Science Association, argued in The New York Times that the Unabomber manifesto alone provided compelling evidence of Kaczynski’s sanity.

There is nothing in the manifesto that looks at all like the work of a madman. The language is clear, precise and calm. The argument is subtle and carefully developed, lacking anything even faintly resembling the wild claims or irrational speculation that a lunatic might produce. […] If it is the work of a madman, then the writings of many political philosophers—Jean Jacques Rousseau, Tom Paine, Karl Marx—are scarcely more sane. (Wilson 1998)

Wilson’s aim was certainly not to defend Kaczynski’s ideas, and neither is mine. His point was that Kaczynski was competent enough to represent himself in court. My point is that Kaczynski was competent enough to be understood as a political actor—a bona fide terrorist. His system of beliefs appears to be no more delusional than any other radical ideology.

The prosecutors accepted that Kaczynski was sane, but they also cast doubt on whether his bombings were politically motivated. In their 1998 Sentencing Memorandum, they argued that the ideology he espoused was a carefully crafted cover for his true motivations—vengeance and hatred. Kaczynski seemed to admit as much in his journal entry of April 6, 1971: “My motive for doing what I am going to do is simply personal revenge. I do not expect to accomplish anything by it. […] I certainly don’t claim to be an altruist or to be acting for the ‘good’ (whatever that is) of the human race” (Kaczynski, quoted in Seave 1998, 38). Yet, the remainder of this journal entry shows that Kaczynski’s desire for “revenge” was political as well as personal. His bombing campaign was an attempt to retaliate against “the system” for encroaching on human freedom: “I would like to get revenge on the whole scientific and bureaucratic establishment, not to mention communists and others who threaten freedom, but, that being impossible, I have to content myself with just a little revenge.” Anticipating the prosecution’s attempt to dismiss his ideological motivations, he added, “some people will deny that I am motivated by a hatred for what is happening to freedom,” but “they are wrong” (Kaczynski, quoted in Seave 1998, 38). Further, Kaczynski’s description of his “personal” motivations was itself laden with ideology. One of his foundational assumptions was that human beings—himself included—were fundamentally self-interested. As he wrote in his journal on May 6, 1985, “anyone who ever makes great efforts or takes great risks on account of social issues has some powerful personal motive, even if he persuades himself that he is actuated by pure altruism” (Kaczynski, quoted in Seave 1998, 41). Thus, although Kaczynski’s bombings were motivated by a desire for “personal revenge,” they were nonetheless ideologically motivated. These two motivations are not mutually exclusive.

In any case, Kaczynski’s psychology can provide only a partial explanation for his bombing campaign. His psychology may help to explain why he became violent, but it cannot explain why he chose the targets he did. His ideology is necessary to explain why he sought “revenge” against scientists and corporate executives rather than, for example, government officials or people against whom he held personal grudges. In this case, as in many others, ideological and psychological explanations for political violence are complementary.

In addition to the general doubts about whether Kaczynski was ideologically motivated, there are more specific doubts about whether he was sincerely committed to his stated ideal of “wild nature” (Kaczynski 1995a, 183). Some previous analyses of the Unabomber manifesto have suggested that the “green” parts are purely rhetorical. Sale (1995, 310) argues that Kaczynski “is no environmentalist”: “his appeal to nature is entirely utilitarian (like adding another little mechanism to your bomb to make sure it works).” Similarly, Chase (2004, 94) argues that Kaczynski’s idea of “wild nature” was “at best, an afterthought,” and “more probably a cynical attempt to win more supporters for his revolution.” Chase points out that Kaczynski’s (1972) essay, “Progress Versus Liberty,” anticipates many of his manifesto’s core ideas but does not even mention nature. He concludes that “Kaczynski had dressed his message in green” only “because he thought it would make his treatise more popular” (Chase 2004, 94). If this is true, then Kaczynski can easily be excluded from the category of environmentalists.

One problem with Chase’s argument is that his timeline is incomplete. The idea of wild nature appears in Kaczynski’s earliest known writings, even before “Progress Versus Liberty.” In a February 1969 letter to The Wilderness Society, he warned that the increasing use of nature for recreation would “make necessary more and more scientific control and manipulation of wilderness areas.” In the end, he lamented, “the areas will not really be wild at all, because every aspect of them will be under the control of man” (Kaczynski, quoted in Turner 2012, 71). A similar understanding of wildness appears in Kaczynski’s (1979) essay, “Progress Versus Wilderness.” There, citing environmental historian Roderick Nash, he defined “wildness” as “that which is not controlled by organized society” (Kaczynski 1979, 2). That idea would later be recast as “wild nature” in his manifesto: “those aspects of the functioning of the Earth and its living things that are independent of human management and free of human interference and control” (Kaczynski 1995a, 183). Far from being an afterthought, the concept of wild nature appears in Kaczynski’s writings over 25 years before the Unabomber manifesto.

In an attempt to show that Kaczynski’s appeal to nature was purely rhetorical, Chase (2004, 94) quotes an apparently damning entry from his journal.

I don’t even believe in the cult of nature-worshipers or wilderness-worshipers. (I am perfectly ready to litter in parts of the woods that are of no use to me—I often throw cans in logged-over areas or in places much frequented by people; I don’t find wilderness particularly healthy physically; I don’t hesitate to poach). (Kaczynski 1978, 7)

The prosecutors also quoted this passage in their Sentencing Memorandum to cast doubt on Kaczynski’s commitment to “wild nature” (Seave 1998, 14). Ironically, however, this passage highlights some of his strongest affinities with environmentalism. It echoes a motif from Edward Abbey’s ([1975] 2004) novel, The Monkey Wrench Gang, which was a major source of inspiration for American radical environmentalists (Lee 1995; Taylor 2008; Woodhouse 2018). Two of Abbey’s protagonists repeatedly throw their beer cans on the road while they engage in sabotage to protect the wilderness from industrial encroachment: “Any road I wasn’t consulted about that I don’t like, I litter. It’s my religion” (Abbey [1975] 2004, 68). Abbey himself was famous for throwing beer cans on the road (Thompson 2014). The point he was trying to make was that the concerns of mainstream environmentalists, such as littering, are merely conscience-cleansing distractions; industrialism is the real threat to wild nature. For Kaczynski, as for Abbey, throwing cans “in places much frequented by people” was a way of throwing industrial society’s byproducts back in its face.

Kaczynski briefly mentioned The Monkey Wrench Gang in a January 1985 journal entry: “Mr. Abbey’s attitude is in some ways similar to mine, though it is not identical” (Kaczynski 1985a, 96). One crucial difference was that Abbey, in line with the Peaceful Environmentalist Thesis, did not condone violence against human beings. The Monkey Wrench Gang’s voice of reason, Dr. Sarvis, repeatedly rebukes his hot-headed comrade, George Hayduke, when he reaches for his gun (Abbey [1975] 2004, 73, 135, 328). What Kaczynski found appealing in Abbey’s work was his anti-industrialism, his political incorrectness, and, most of all, his understanding of freedom as wildness. For Abbey, wilderness was a place where human beings could be free: “To the question: Wilderness, who needs it? Doc would say: Because we like the taste of freedom, comrades” (Abbey [1975] 2004, 261). Kaczynski expressed a similar idea in “Progress Versus Wilderness”: “wilderness provides the most important opportunity to experience wildness” (Kaczynski 1979, 2). The Unabomber manifesto is centrally concerned with “freedom,” understood as the ability to live in accordance with wild human nature, or natural human instincts (Kaczynski 1995a, 33–7, 93–8).

When Kaczynski wrote in his journal that he rejected “the cult of nature-worshipers or wilderness-worshipers” (Kaczynski 1978, 7), the operative word was “worship.” He rejected spiritual understandings of nature and idealized visions of nature untouched by humanity (Kaczynski 2003b; 2010). In Kaczynski’s “wild nature,” “wild” is the dominant term: the freedom permitted by an environment is more important than whether it is pristine. In a 2004 letter, he argued that “wild nature can better be experienced on a piece of abandoned or neglected wasteland—even one that has been ravaged by logging or mining—than in a consciously preserved wilderness such as a national park.” Whereas visitors to a national park are subject to rules and supervision, people can live freely on wasteland: “one can gather edible plants, kill small animals for food, cook over an open fire, build a shelter of naturally-available materials in a place of one’s own choosing… in short, one can get off the leash” (Kaczynski 2004, 7, ellipse in original). Poaching was Kaczynski’s way of living in accordance with his understanding of wild nature, “off the leash” and onto the food chain.

In sum, the claim that the “green” parts of the Unabomber manifesto are purely rhetorical does not stand up to scrutiny. The evidence shows that Kaczynski was sincerely committed to “wild nature”—a concept that he borrowed from Roderick Nash, an eminent environmental historian—and the apparently anti-environmentalist passages in his journal actually echo themes from radical environmentalist literature.

Radical Environmentalism

“Radical environmentalism” is a catch-all category for environmental activists who reject the anthropocentric assumptions of modern society. Although their tactics and philosophical positions vary, what unites radical environmentalists is their commitment to the intrinsic value of nonhuman life. In Kaczynski’s time, the most prominent radical environmentalist group was Earth First!, which was founded in 1980 and led by Dave Foreman, a former lobbyist for The Wilderness Society. Earth First!ers were notorious for their use of “monkeywrenching,” or small-scale sabotage, to disrupt logging operations, and many of their detractors called them “ecoterrorists.”[3]

Kaczynski is often called a radical environmentalist (Arnold 1997; Barnett 2015). Journalists have long speculated that he was inspired or incited by groups such as Earth First! (e.g., Bailey 2021; Chavez 1996; Lileks 1996). Two facts lend plausibility to these claims. First, Kaczynski read radical environmentalist publications, including the Earth First! Journal and Live Wild or Die, and he apparently used information from the latter to select some of the targets of his bombings (Chase 2004, 73–7). Second, the Unabomber manifesto’s central antithesis—“wild nature” versus “industrial society”—featured prominently in 1980s radical environmentalist discourse. As Kaczynski (1995a, 184, emphasis in original) acknowledged, “radical environmentalists already hold an ideology that exalts nature and opposes technology”—though it is notable that he did not identify as one of them.

As it turns out, Kaczynski borrowed very few of his ideas from radical environmentalists. He had not heard of Arne Naess or George Sessions, the intellectual pioneers of Deep Ecology, until after his arrest (Kaczynski 2001a).[4] He had not heard of Earth First! until about 1987, approximately seven years after the group emerged (Kaczynski 2008, 4–5). By that time, his bombing campaign had been underway for nearly a decade, and his own ideology was well developed (Kaczynski 1972; 1979). He was drawn to radical environmentalist literature because it expressed anti-industrial views that he already held.

Kaczynski’s concept of wild nature is, as I have argued, a genuine intellectual-historical link to environmentalism. However, the fact that his stated ideal was “wild nature” does not make him an environmentalist, any more than the fact that he championed “freedom” makes him a liberal. First of all, an ideology cannot be defined according to a single concept, because most ideologies have substantial conceptual overlaps (Freeden 1996, 83). Second, terminological similarities often conceal important conceptual differences: “identical words may mask unbridgeable conceptual and behavioral divides” (Freeden 1996, 53). Kaczynski’s understanding of wild nature was different from that of radical environmentalists, and it was nested within a very different configuration of concepts.

Radical environmentalists tend to understand nature as a harmonious balance among organisms and species. As Humphrey (2013, 425) observes, “Ecology is taken to show the value of symbiosis and mutual cooperation (Greens are more Kropotkinite than Darwinist).” For Earth First!ers, the concept of “wild nature” was embedded in the spiritual worldview of Deep Ecology, which emphasizes symbiosis, diversity, and equality (Naess 1977). Kaczynski, on the other hand, understood “wild nature” (including human nature) in Darwinian terms, as the product of a competitive and often violent struggle for survival. “Since man has been a hunter for the last million years,” he speculated in a 1985 letter to his brother, “it is possible that, like other predatory animals, he has some kind of a ‘killer instinct’” (Kaczynski 1985b, 3; see also Kaczynski 2003c, 8–9). As Humphrey (2013, 425) implies, the difference between “Kropotkinite” and “Darwinist” understandings of nature is a matter of emphasis. Although some radical environmentalists do invoke Darwinian ideas, they nonetheless tend to reach Kropotkinite conclusions. For example, although the conservationist Aldo Leopold borrowed many of his ideas about ecology from Darwin himself (Millstein 2015), his “land ethic” emphasizes the role of interdependence and the potential for cooperation in nature (Leopold 2020, 155–7). Where Leopold saw a “biotic community,” Kaczynski saw a battle for survival.

Kaczynski’s hyper-Darwinian understanding of nature helps to explain why he differed from radical environmentalists on the question of violence. As Taylor (1998, 14) observes, radical environmentalists share “general religious sentiments—that the earth and all life is sacred—that lessen the possibility that movement activists will engage in terrorist violence.” Their commitment to the sanctity of life presents an ideological barrier against killing people. For this reason, the characteristic modi operandi of radical environmentalists are sabotage and civil disobedience (Hirsch-Hoefler and Mudde 2014; Loadenthal 2014; 2017; Sumner and Weidman 2013). Dave Foreman of Earth First! implored environmental saboteurs never to harm living beings: “Monkeywrenching is nonviolent resistance to the destruction of natural diversity and wilderness. It is never directed against human beings or other forms of life” (Foreman 2002, 9). Even the Earth Liberation Front, which was notorious for its firebomb attacks against industry, strictly adhered to this principle: “The ELF considers itself a non-violent organization as no physical harm has come to a human as a result of the group’s actions” (ELF 2001, 15). A few radical environmentalist groups, such as Deep Green Resistance, have argued that lethal violence is justified and even necessary to prevent a global ecological catastrophe (McBay, Keith, and Jensen 2011). But none, so far, seem to have followed through on their bellicose rhetoric. In his June 1995 cover letter to The New York Times, Kaczynski himself acknowledged that “radical environmentalists do engage in sabotage” but, unlike him, “the overwhelming majority of them are opposed to violence against human beings” (Kaczynski 1995c, 2).

As Taylor (1998, 17) says, there is “no indication that Kaczynski shared the sense, so prevalent in radical environmental subcultures, that life is worthy of reverence and the earth is sacred.” Although Taylor is right that there is a deep ideological difference here, it is more subtle than he suggests. “Yes, I have reverence for life, understood as the totality of life on Earth,” Kaczynski (2003a, 1) wrote in a revealing letter. However, he added that “death and killing are parts of the totality of life.” Whereas radical environmentalists’ Kropotkinite understandings of nature gave rise to an ethic of nonviolence, Kaczynski’s hyper-Darwinian understanding of nature served to naturalize and justify his violence. As he wrote in another letter, “Human beings in the wild constitute one of the more violent species. […] a significant amount of violence is a natural part of human life” (Kaczynski 2003c, 8–9).

On the whole, there are few intellectual links or conceptual similarities between Kaczynski’s ideology and radical environmentalism. Although they share the term, “wild nature,” identical words conceal an important conceptual difference. Further, Kaczynski’s concept of wild nature is embedded in a different network of concepts. None of the Unabomber manifesto’s three signature concepts—“the power process,” “surrogate activity,” and “oversocialization”—are derived from environmentalist sources (Fleming 2022).

“The power process” encapsulates Kaczynski’s understanding of human nature: “a human being needs goals whose attainment requires effort, and he must have a reasonable rate of success in attaining his goals” (Kaczynski 1995a, 37). In “primitive” societies, human beings satisfied their need for the power process by struggling “to obtain the physical necessities of life: food, water and whatever clothing and shelter are made necessary by the climate” (Kaczynski 1995a, 35). Since industrialization has reduced the struggle for survival to triviality, at least in “‘advanced’ countries,” people try to satisfy their need for the power process through “surrogate activities,” such as hobbies, sports, research, and activism (Kaczynski 1995a, 38–41). Kaczynski argued that “these artificial forms of the power process are insufficient,” which is why feelings of purposelessness and alienation are so widespread in modern society (Kaczynski 1995a, 64). In addition, the power process is disrupted by “oversocialization,” or the excessive inculcation of social norms. Many natural human impulses and tendencies—hatred, anger, violence, and nepotism—must be suppressed, because they interfere with the functioning of complex organizations and systems of production. For “oversocialized” people, who have deeply internalized the norms of equality, impartiality, and nonviolence, “the attempt to think, feel, and act morally imposes a severe burden” and “results in a sense of constraint and powerlessness” (Kaczynski 1995a, 25–6). Kaczynski thus attributed the widespread psychological problems in modern society—from depression and anxiety to eating disorders and substance abuse—to the fact that “society requires people to live under conditions radically different from those under which the human race evolved” (Kaczynski 1995a, 46).

Whereas radical environmentalists oppose modern technology for ecological reasons, Kaczynski opposed modern technology primarily for evolutionary-psychological reasons. He recognized this difference from the very beginning. At first, seeing nowhere else he might find fellow anti-tech radicals, he tried to find them in environmentalist groups. Kaczynski corresponded with Friends of the Earth in the 1970s—“not because I think such organizations do any good,” he wrote in his journal, “but because there might be a chance I could meet some people in that organization who would share my antitechnological views” (Kaczynski 1978, 12, emphasis in original). With the same instrumental motivation, he wrote an essay titled “Suggestions for Earth First!ers from FC” (Kaczynski N.d.). His aim was to persuade Earth First!ers that technology as such was the problem, and that the preservation of wilderness was only a side-issue. He framed his argument as advice about strategy: “as long as you fight only on environmental and wilderness issues you are fighting defensively […] to fight offensively you’ve got to get out of the woods and attack the structures that make the system run” (Kaczynski N.d., 3, emphasis in original). Kaczynski argued that “the Earth First! journal should devote at least half its content to questions that have central relevance to the development of the industrial-technological system”—in particular, “genetic engineering,” “computer technology,” and “propaganda” (Kaczynski N.d., 2). Behind the pretense of offering strategic advice, he was apparently trying to steer the group from pro-ecological toward anti-technological objectives.

Kaczynski eventually gave up trying to convert radical environmentalists and instead began to emphasize the differences between his ideology and theirs. In his 2016 book, Anti-Tech Revolution, he encouraged his followers to carve out a distinct identity: “One movement from which an anti-tech organization needs to separate itself definitively is that of the radical environmentalists; another is anarchoprimitivism” (Kaczynski 2016, 167). Although there might be strategic reasons for an anti-tech organization to collaborate with radical environmentalist groups—“to attract recruits,” “for the propagation of anti-tech ideas,” for “training and experience,” or “to take over a radical environmentalist group,” as Kaczynski wanted to do with Earth First!—members of the anti-tech organization “will need to understand that their purpose in working with radical environmentalists is solely to win advantages for anti-tech” (Kaczynski 2016, 172–3).

Although it is understandable how Kaczynski could be mistaken for a radical environmentalist, this perception is more of a deliberate fabrication than an honest mistake. In the mid-1990s, conservative political commentators branded Kaczynski an environmentalist because it was a convenient way to tarnish their political adversaries. After Timothy McVeigh, an anti-government extremist, carried out the Oklahoma City Bombing in April 1995, the American left blamed the Republican Party and the National Rifle Association (Klein 1996). In September 1995, when “Industrial Society and Its Future” was published, the right retaliated by blaming environmentalists for the Unabomber. Tony Snow, the host of Fox News Sunday and a former speechwriter for George H. W. Bush, compared Kaczynski to then-Vice President Al Gore: “the most striking thing is how much [the manifesto] sounds like Al Gore’s book, Earth in the Balance” (Snow 1995). Many others jumped on the bandwagon, blaming “liberals” in general and environmentalists in particular for the Unabomber (e.g., Arnold 1997; Chavez 1996; Lileks 1996; Thomas 1996). The branding of Kaczynski as an “ecoterrorist” is, in large part, a calcified piece of political rhetoric from the 1990s.

Green Anarchism

In his Unabomber communiqués, Kaczynski identified as an anarchist, without prefixes or adjectives. As he explained in his April 1995 letter to The New York Times, “We call ourselves anarchists because we would like, ideally, to break down all society into very small, completely autonomous units” (Kaczynski 1995b, 1). This emphasis on autonomy and decentralization, combined with the ideal of “wild nature,” evokes green anarchism or anarcho-primitivism (Kallenborn and Bleek 2020, 363–4; Woodhouse 2014, 11–2). Indeed, some green anarchists initially saw the Unabomber as one of their own. John Zerzan, an influential anarcho-primitivist based in Eugene, Oregon, became one of Kaczynski’s staunchest defenders and closest confidants (Noble 1995; Zerzan 1995).[5]

Placed in the category of anarchism, Kaczynski’s violence is somewhat more legible. Although most contemporary anarchists reject violence, anarchists were notorious for using bombs to assassinate people in the late nineteenth and early twentieth centuries. The Unabomber campaign looks like a revival of “propaganda by the deed.” As Taylor (2003, 181) says, “the anarchist movement provides more fertile ground for violent tactics than those who identify chiefly with radical environmentalism.” However, he adds, green anarchists appear unwilling to go beyond “sporadic arson and small-scale (non-lethal) violence in street battles with the police” (Taylor 2003, 181). While some green anarchists supported Kaczynski as a political prisoner, they had serious reservations about his violence. Zerzan’s (1995) criticism of the Unabomber summed up a common sentiment in the movement: “the mailing of explosive devices intended for the agents who are engineering the present catastrophe is too random. Children, mail carriers and others could easily be killed. Even if one granted the legitimacy of striking at the high-tech horror show by terrorizing its indispensable architects, collateral harm is not justifiable.” Kaczynski’s bombing campaign was uncharacteristic of green anarchists. As with radical environmentalism, this difference in tactics is a sign of deeper ideological differences.

Kaczynski’s intellectual links to anarchism are even weaker than his links to radical environmentalism. He does not appear to have read any of the major figures in the anarchist tradition, such as Pierre-Joseph Proudhon, Mikhail Bakunin, Peter Kropotkin, Rosa Luxemburg, Emma Goldman, Alfredo Bonanno, and Errico Malatesta. Kaczynski had not even heard of Zerzan until after his arrest (Kaczynski 2001a). Only one recognizable (albeit atypical) anarchist appears prominently in Kaczynski’s paper trail: Jacques Ellul, a French sociologist who is often labeled a Christian anarchist. Kaczynski borrowed or adapted many of his ideas from Ellul (Corey 2000; Fleming 2022). But Kaczynski had not read any of Ellul’s books on anarchism by the time he wrote his manifesto—only Ellul’s books on technology, propaganda, and revolution (Kaczynski 2001a). Kaczynski’s self-identification as an anarchist likely had a literary inspiration. He identified with the anarchist characters in his favorite novel, Joseph Conrad’s The Secret Agent, apparently without realizing that Conrad was satirizing anarchism (Foster 1998; Guimond and Kearney Maynard 1999). Wherever he found the anarchist label, Kaczynski’s links to the anarchist tradition are tenuous, as he admitted in his June 1995 letter to The New York Times: “We decided to call ourselves anarchists not in order to associate ourselves with any particular anarchist group or movement but only because we felt we needed some label to apply to ourselves and ‘anarchist’ was the only one that seemed to fit” (Kaczynski 1995c, 2).

Yet, the morphological “fit” between Kaczynski’s ideology and anarchism is fairly superficial. Kaczynski shared anarchists’ disdain for “large organizations,” such as states and corporations, and their preference for a society of “small groups” (Kaczynski 1995a, 215). He believed, as many green anarchists do, that life in “primitive” societies was more authentic and fulfilling than modern life (Kaczynski 1995a, 75). But beneath these general points of convergence are much more fundamental differences.

First, Kaczynski did not use the conceptual vocabulary of anarchism. The key terms in the anarchist lexicon, such as “mutual aid,” “oppression,” “domination,” “exploitation,” and “solidarity,” are strikingly absent from his writings. Only one of his signature concepts has a rough equivalent in anarchist discourse. Kaczynski’s concept of “oversocialization,” like the anarcho-primitivist concept of “domestication,” denotes a condition in which authentic human nature has been socially suppressed. His other two signature concepts—“the power process” and “surrogate activity”—have no parallels in the anarchist vocabulary.

Second, whereas equality stands at the core of anarchism, it is not even part of the periphery of Kaczynski’s ideology. He discussed issues of inequality and social injustice in his manifesto only to mock and dismiss them as “leftist” and “reformist” (Kaczynski 1995a, 6–32, 213–30). Further, the vanguardist revolution that Kaczynski proposed, led by “a small core of deeply committed people” (Kaczynski 1995a, 189), stands in stark tension with the egalitarian, participatory ethos of anarchism. The Editors of Green Anarchist (1996, 27) described Kaczynski’s theory of revolution as “unpleasantly elitist.” Other anarchists went further, condemning it as “authoritarian” (e.g., Moore 1998; Starcross 1998; Primal Rage 2002). As an anarchist named “Iain” (1999/2000, 76) argued in Anarchy: A Journal of Desire Armed, Kaczynski’s plan to overthrow the technological system “may be revolutionary, but it is not anarchism.”

Third, Kaczynski defined his enemy much more narrowly than green anarchists do. His goal was to destroy “the industrial-technological system,” understood as an interconnected assemblage of machines and techniques (Kaczynski 1995a, 121–4). As expansive as Kaczynski’s concept of “the system” is—encompassing everything from computers and refrigerators to techniques of advertising and management—green anarchists’ concept of “civilization” is even broader. For them, technology is only one facet of “civilization”; equally important are racism, sexism, colonialism, and a multitude of other forms of domination (Faun 1997; Zerzan 1994). Kaczynski fell out with green anarchists mainly because of a rift about these “leftist” issues. “If you think that women’s issues, black people’s issues, gay rights, animal rights, etc., etc., etc., etc., etc. are more important than getting rid of the technosystem,” Kaczynski (2001b, 3) chided Zerzan, “then I suggest you confine your attention to those issues and leave the technology problem to the people who are serious about it.” Zerzan countered that “there needs always to be a fundamental criticism of any single-issue-ism,” emphasizing “the inter-relatedness of oppressions/issues” (Zerzan 2003, 1, emphasis in original). Similarly, Starcross (1998, 15) argued in Green Anarchist that Kaczynski’s actions “are ultimately worthless” because they “result from a partial critique of power.”

Although Kaczynski was definitely a primitivist, he was never an anarcho-primitivist.[6] He eventually came to regret that he had called himself an anarchist: “I am not pleased to see ISAIF [Industrial Society and Its Future] associated with anarchism. When I wrote ISAIF I adopted an anarchist identity because I thought it would be helpful to pin some sort of recognized political identity on ISAIF. That was a big, big mistake!” “At the time,” he added, he “knew very little about anarchism as a political movement” (Kaczynski 2012, 1–2, emphasis in original; see also Kaczynski 1995c). Many anarchists, for their part, have come to see Kaczynski as a reactionary. Summing up a common sentiment in the movement, the Detroit-based anarchist newspaper, Fifth Estate, condemned Kaczynski’s “fascistic comments” about the left and his “racist, macho writings” (Fifth Estate Collective 2016).

Right-Wing Ecologism

Given his antipathy toward the left and his call for a return to nature, Kaczynski can plausibly be read as a right-wing ecologist, if not a bona fide ecofascist (Rueda 2020). He has had a significant influence on the far right, especially its “green” factions (Hughes, Jones, and Amarasingam 2022; Macklin 2022). Pentti Linkola, one of the most influential ecofascists, has praised Kaczynski’s “planned, thoughtful model for an alternative society” (Linkola 2011, 159).

Placed within the category of right-wing ecology, Kaczynski’s use of lethal violence no longer appears exceptional. “The only thing that is effective, which weakens and shocks the current order bent on world destruction, is extreme violence,” Linkola (2011, 170) infamously declared. Self-described ecofascists have recently carried out several deadly attacks, including the 2019 mosque shooting in Christchurch, New Zealand, the 2019 Walmart shooting in El Paso, Texas, and the 2022 supermarket shooting in Buffalo, New York (Amend 2020; Moore and Roberts 2022).

Staudenmaier (2021) has developed the most sophisticated right-green interpretation of Kaczynski. He places the Unabomber manifesto in the context of “anti-industrial and proto-ecological thinking on the German right” (Staudenmaier 2021, 52). Following conservative thinkers such as Ludwig Klages, Oswald Spengler, and Friedrich Georg Jünger, Staudenmaier argues, Kaczynski belongs to the tradition of “right-wing Kulturkritik and Zivilisationskritik, the reactionary critique of civilization as such” (Staudenmaier 2021, 53). If he was not quite an ecofascist, he was nonetheless a figure of right-wing ecology.

As an account of Kaczynski’s intellectual influences, this right-green reading is speculative. There is no evidence that Kaczynski read, or was even aware of, Klages, Spengler, or Jünger. (He was aware of Martin Heidegger—the most famous figure of the proto-ecological German right—but detested him. Kaczynski reportedly became incensed when his brother, David, “became a convert” to Heidegger [Chase 2004, 107]). As Staudenmaier (2021, 69) admits, the affinities that he identifies “are not a matter of direct ideological influence; there is little indication that Kaczynski was familiar with this literature.” But identifying conceptual parallels will have to suffice, Staudenmaier (2021, 50) says, because “we have little direct information about what Kaczynski may have read.” In fact, there is a wealth of direct information about what Kaczynski read, spanning over 50 years. The archival record does not show any discernable links between Kaczynski and the proto-ecological German right, let alone direct lines of intellectual influence. His critique of technology is derived mainly from the French sociologist Jacques Ellul—an avowed figure of the left, who counted Marx as one of his main influences. Kaczynski found his rugged understandings of human nature and freedom not in conservative political thought, but in popular science. His ideas of “the power process” and “surrogate activity” are derived from the British zoologist Desmond Morris and the American psychologist Martin Seligman, while his idea of “oversocialization” appears to be borrowed from the French biologist René Dubos (Fleming 2022). What is striking about Kaczynski is how little he seemed to know or care about the vast and influential German tradition of technological critique.

As an account of Kaczynski’s ideological morphology, the right-green interpretation does not fare much better. Right-wing ecologists are drawn to him because of some obvious points of affinity: reverence for nature, opposition to modern technology, and disdain for the left. However, Kaczynski’s ideology lacks two of the core features of the right-wing ecology.

First, and most importantly, Kaczynski rejected the ideas of racial supremacy and national solidarity that lie at the heart of right-wing ecology. Spengler’s (1932, 101–2) worry about modern technology was that “the colored races” would use it to overturn the dominance of “the white races,” as Japan did in the 1904–1905 Russo-Japanese War. “Instead of keeping strictly to itself the technical knowledge that constituted their greatest asset,” he lamented, “the ‘white’ peoples complacently offered it to all the world.”

The unassailable privileges of the white races have been thrown away, squandered, betrayed. The others have caught up with their instructors. […] The innumerable hands of the coloured races—at least as clever, and far less exigent—will shatter the economic organization of the whites at its foundations. (Spengler 1932, 101–2)

Kaczynski (1995a, 195) mocked such fears of foreign domination, calling them “hysterical”: “Holy robots! The world will fly off its orbit if the Japanese ever sell more cars than we do!” He acknowledged that attempting to overthrow the technological system in the United States might allow “nasty, dictatorial nations like China, Vietnam and North Korea,” with their technology intact, to dominate America (Kaczynski 1995a, 195). But this was of little concern to him because he saw little difference between one form of technological society and another. He even suggested that “an industrial system controlled by dictators may be preferable, because dictator-controlled systems usually have proven inefficient; hence, they are presumably more likely to break down”—“Look at Cuba” (Kaczynski 1995a, 195). “Nationalism is a great promoter of technology,” Kaczynski (1995a, 195) warned, because international competition and conflict drive technological arms races.

Second, whereas population control is central to right-wing ecology, Kaczynski saw overpopulation as a peripheral concern or even a distraction from the problem of technology. Since the Second World War, Spengler’s (1932, 102) alarm about the “innumerable hands of the colored races” has given way to more cryptically racist forms of neo-Malthusianism. American ecologist and eugenicist Garrett Hardin (1974) famously compared “rich nations” to “lifeboats,” which would sink if too many people from “poor nations,” with much higher birth rates, were allowed to come aboard. Linkola (2011, 130) spelled out the implications of Hardin’s metaphor in graphic detail: “When the lifeboat is full, those who hate life will try to pull more people onto it, thus drowning everyone. Those who love and respect life will instead grab an axe and sever the hands clinging to the gunwales.” As far as Linkola (2011, 170) was concerned, the “lifeboats” were already over capacity, and their human loads had to be “forcibly made lighter.” Kaczynski, on the other hand, rejected neo-Malthusianism. Although he “would rather see a world with only one-thousandth as many people as it has now,” he saw “overpopulation [as] only a symptom” of the technology problem (Kaczynski 2009, 2). As he wrote in his manifesto, “the most important problem is to get rid of the industrial system, because once the industrial system is gone the world’s population necessarily will decrease.” In the meantime, he argued, “Revolutionaries should have as many children as they can” (Kaczynski 1995a, 205). Further, Kaczynski pointed out that population control and opposition to modern technology do not necessarily go together: “there’s no reason why population can’t be reduced even while modern technology is retained. […] the overcrowding argument is less likely to lead people to reject technology than to seek more effective means of reducing the world’s population” (Kaczynski 2011, 1). After all, China implemented its one-child policy during a period of unprecedented economic growth and technological development. Kaczynski was wary of population control, because it provided a powerful impetus for medical technology and techniques of social control.

Alarmed by the fact that many right-wing ecologists have adopted him as an icon, Kaczynski (2020) wrote an essay titled “Ecofascism: An Aberrant Branch of Leftism.” There he condemned both “ordinary leftists” and ecofascists for being “fixated on race” (Kaczynski 2020, 3). He emphasized that the anti-tech movement “must make every effort to minimize divisions or differences among races or ethnic groups,” and that “racial and cultural blending must be promoted” (Kaczynski 2020, 3, emphasis in original). His critique of ecofascism parallels his critique of leftism. When he wrote in his manifesto that “the single, overriding goal must be the elimination of modern technology, and that no other goal can be allowed to compete with this one” (Kaczynski 1995a, 206), he deliberately cast a broad net. Social justice activism was his prime illustration of how other goals “distract attention and energy from the main goal” (Kaczynski 1995a, 200), but he applied the same principle to nationalism and racial supremacy. “The goals of nationalism and ethno-nationalism are the goals only of fools,” he admonished an anonymous correspondent in 2018. “Such goals only distract attention from the one goal that is overwhelmingly more important than all other goals put together”—namely, “to get rid of the technological system before it gets rid of us.” He added that he was “firmly opposed to any notions of ethnic, racial, or gender ‘superiority’ or ‘inferiority,’” and that “any successful effort to get rid of the technological system will have to span all races, ethnic groups, genders, etc.” (Kaczynski 2018, 1–2). In Kaczynski’s one-track mind, technology was the problem of the modern world, and everyone who failed to recognize this—liberals, conservatives, anarchists, and fascists alike—was to be swept into the same dustbin.


What, then, was Kaczynski’s relationship with environmentalism? The null hypothesis—that there was no relationship—does not stand up to the archival evidence. However, Kaczynski defies the three eco-ideological labels that are commonly applied to him. His ideology displays only weak morphological affinities with radical environmentalism, green anarchism, and right-wing ecologism, and it has only weak intellectual-historical connections to the environmental tradition. With the lone exception of “wild nature,” none of his core concepts or even peripheral concepts are derived from environmentalist sources. Kaczynski’s ideology might be considered a second or third cousin of environmentalism, because it does have some common intellectual lineage, but its conceptual structure and motivating concerns are fundamentally different.

If Kaczynski was not an environmentalist, then what was he? Although it is beyond the scope of this article to provide a detailed answer to this question, I have already gestured at an answer. One of the distinguishing features of Kaczynski’s ideology is that it is single-mindedly anti-technological. While many green anarchists, ecofascists, and radical environmentalists take anti-technological positions, they do so contingently, as a consequence of other ideological commitments. Green anarchists might be pro-technology if they believed that new technologies were more conducive to human equality and harmonious coexistence with nature than to surveillance, social control, and domination of nature. Ecofascists might be pro-technology if they believed that technology could be kept in the hands of their own nation and used for selective population control. Radical environmentalists might be pro-technology if they believed that green technology could solve climate change and help to preserve what remains of the wilderness. Indeed, some anarchists, fascists, and environmentalists are pro-technology. However, there is no simple permutation of belief that would have made Kaczynski pro-technology; this would have required a fundamental change in his worldview. “It is conceivable,” Kaczynski (1995a, 139) readily admitted, “that our environmental problems (for example) may some day be settled through a rational, comprehensive plan.” But he would still have wanted to destroy the technological system, because rational environmental management is antithetical to “wildness” and “freedom.” This, in a nutshell, is what distinguishes Kaczynski’s anti-tech radicalism from many varieties of environmentalism.

What is to be made of the Peaceful Environmentalist Thesis? On the one hand, Kaczynski is not a credible counterexample to the generalization that environmentalists do not use lethal violence. He is better understood as an anti-tech terrorist than as an ecoterrorist. On the other hand, Kaczynski highlights another class of apparent counterexamples to the Peaceful Environmentalist Thesis: ecofascists. It could be argued that ecofascists are not genuine counterexamples, either. As Christ (2021) points out, their motivations and modus operandi appear to be more “fascist” than “eco”: “Rather than attacking oil pipelines or hydroelectric dams, self-professed ‘ecofascists’ like Tarrant [the Christchurch shooter] attack the same kinds of people and places as non-environmentalist right-wing terrorists.” However, there is a danger here of committing the “no true Scotsman” fallacy. It is tempting to defend the Peaceful Environmentalist Thesis by denying that alleged counterexamples represent “true” environmentalism. If ecofascists are to be excluded from the category of environmentalists, then this must be justified by morphological and genetic ideology analysis.

In any case, the Peaceful Environmentalist Thesis should be carefully qualified. Based on the available evidence, the most that can be said with confidence is that many environmentalists have a strong aversion to the use of violence against human beings. The commitment to a harmonious, egalitarian understanding of nature seems to be the crucial factor (Taylor 1998; 2003; 2004). As the case of the Unabomber shows, not all nature-centered ideologies are inherently peaceful; nor are they necessarily environmentalist. Darwinian understandings of nature can easily be used to justify and naturalize violence. Further, as Linkola (2011) shows, even Deep Ecology can be interpreted in a way that legitimizes violence. If the goal of preserving maximum biodiversity is taken to be absolute, then any number of individual organisms can be culled to prevent the extinction of species (Ferré 1996; Lo 2001). By Linkola’s ruthless logic, the life of one endangered owl is worth more than the lives of a billion human beings. Although environmental activists have so far been reluctant to cross the line between ecotage and ecoterrorism, it is possible, even likely, that some environmentalists will resort to lethal violence in the future. Whether the ethic of nonviolence prevails in the environmental movement will depend on which understandings of nature—cooperative or competitive, Kropotkinite or Darwinian—become more prevalent in the movement in years to come.

In addition to its substantive contributions to the study of political violence and political ideologies, this article makes two methodological contributions. First, it demonstrates how ideology analysis can complement incident-based analysis of terrorists’ tactics and tendencies. Quantitative studies of terrorism rely on qualitative judgments about terrorists’ ideologies, and these judgments are often made in impressionistic ways. The Unabomber has thus been “coded” as an environmentalist, based on little more than popular perceptions and cursory readings of his manifesto. As I have shown, approaches to ideology analysis from political theory can be used to categorize terrorists’ ideologies more systematically.

The second methodological contribution of this article is to demonstrate the promise of forensic ideology analysis. In part, I have followed a path cut by intellectual historians, who have long used archival evidence to trace the origins of ideas. As I have shown, the same kind of evidence is useful for analyzing the conceptual structures of ideologies. The Unabomber case provides an ideal testing-ground for forensic ideology analysis, because Kaczynski has left an exceptionally long paper trail that is full of “smoking guns.” An important lesson from this case is that contextual analysis of ideas—the interpretation of texts in historical context—is necessary but insufficient. Contextual analysis is always necessary, because even the hardest evidence requires interpretation. But contextual analysis without hard evidence is speculative. Although the radical environmentalist, green anarchist, and right-wing ecologist interpretations of Kaczynski all seem consistent with the text of his manifesto and sensitive to the historical context, none of them stand up to the archival record. Spurious claims about a writer’s ideological formation or intellectual influences can easily sound plausible when they are backed by terminological comparisons, tied to the writer’s biography, and framed by broader political and intellectual trends. Much of what historians of political thought call “context” is what detectives would call “highly circumstantial evidence.” Forensic analysis aims to separate contextual interpretations that are merely speculative from those that are supported by hard evidence. The common claims about Kaczynski’s relationship with environmentalism were never more than hunches and half-truths, often asserted with an excess of confidence, but they stood unchallenged for two decades because the forensic evidence had not yet been brought to light. The Unabomber case makes one wonder how many spurious claims about other writers—from Plato to Hobbes to Arendt and beyond—stand unchallenged because the forensic evidence remains buried or no longer exists.


“Searching for Ecoterrorism” cites material from two archives: the Joseph A. Labadie Collection at the University of Michigan and the UNABOM Collection at Pennsylvania Western University. This Appendix describes these archives and explains how to access them.

The Joseph A. Labadie Collection

The Labadie Collection is housed in the Special Collections Research Center at the University of Michigan’s Hatcher Graduate Library. It is one of the largest collections of material related to “radical” political movements in the United States. The Ted Kaczynski Papers were donated to the Labadie Collection by Kaczynski himself, following a request from the archivist, Julie Herrada.[7] The archive opened in 2000. The Kaczynski Papers consist of nearly 100 file boxes of material, including Kaczynski’s publications, journals, autobiographies, notes, drafts, unpublished essays, legal documents, and correspondence. A detailed finding aid is available online.[8] I have cited material from the Kaczynski Papers according to the box and folder numbers, which are listed in the finding aid.

The Kaczynski Papers are under copyright. Researchers may be permitted to take scans of documents, but only for their personal use. Until Kaczynski’s death in June 2023, he retained the copyright; it is now held by an unknown heir, as determined by his last will and testament. Except for some interview tapes and transcripts (which I have not cited), researchers can access the Kaczynski Papers without special permission. Scans of up to two file folders per month can be ordered, free of charge, from the University of Michigan’s Special Collections Research Center.

The UNABOM Collection

The UNABOM Collection is housed at Pennsylvania Western University, California. This collection consists of six file boxes of material that were donated to the Pennsylvania Center for Investigative and Forensic Sciences in 2021 by James R. Fitzgerald, a forensic linguist and former FBI agent who played a pivotal role in the Unabomber case. The UNABOM Collection is divided into four document series: the “C-documents,” which were confiscated from Kaczynski’s cabin; the “T-documents,” which include other writings by Kaczynski; the “U-documents,” which were mailed by the Unabomber; and “Miscellaneous Materials,” including FBI reports and analyses. I have cited material from the UNABOM Collection according to the document series and document number (e.g., U-12).

The UNABOM Collection has been digitized and is available online through Pennsylvania Western University.[9] The donor has confirmed that this digital archive includes all of the material in the physical archive.

Some of the material in the Labadie Collection and the UNABOM Collection has been reproduced on websites, such Yahoo News and The Anarchist Library, without permission. Researchers should be wary of these reproductions not only for copyright reasons, but also because they may be inauthentic, incomplete, or inaccurately transcribed.


I would like to thank three anonymous reviewers and Bron Taylor (who revealed his identity) for their exceptionally thoughtful and constructive comments. I would also like to thank Giovanni Mantilla for translating some Spanish-language material for me. I am especially grateful to Julie Herrada, Curator of the Joseph A. Labadie Collection, and the staff at the University of Michigan’s Special Collections Research Center for making this research possible. I am grateful to William P. Heidrich for funding my visit to the Labadie Collection.

Funding Statement

This research was funded by a William P. Heidrich Visiting Research Fellowship from the University of Michigan.

Conflict of Interest

The author declares no ethical issues or conflicts of interest in this research.

Ethical Standards

The author affirms that this research did not involve human subjects.


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[1] The Unabomber case might be called a “crucial counterexample,” in contrast to what Gerring (2007) calls “confirmatory,” “disconfirmatory,” and “pathway” crucial cases.

[2] See the Supplementary Material and Herrada (2003) for further information about the Labadie Collection’s Kaczynski Papers.

[3] On the history of Earth First! and radical environmentalism, see Lee (1995), Taylor (2008), and Woodhouse (2018).

[4] Kaczynski’s notes cannot be taken at face value, because authors may downplay or simply misrecall their intellectual influences. However, Kaczynski’s claims about what he had and had not read appear to be credible: none of them are contradicted by the extensive body of archival evidence.

[5] Kaczynski’s relationship with Zerzan was complicated, and I cannot adequately summarize it here. Kaczynski’s correspondence with Zerzan is available in the Labadie Collection, University of Michigan, Boxes 14 and 15.

[6] I have suggested elsewhere that “bioprimitivism” is an apt label for Kaczynski’s ideology (Fleming 2022).

[7] Julie Herrada, “Letters to the Unabomber: A Case Study and Some Reflections,” Archival Issues 28, no. 1 (2003/2004): 35-46.

[8] “Ted Kaczynski Papers, 1996-2014 (majority within 1996-2005),” University of Michigan Library Finding Aid, https://findingaids.lib.umich.edu/catalog/umich-scl-kaczynski (accessed December 20, 2023)

[9] “UNABOM Collection,” Pennsylvania Western University Islandora Site, https://harbor.klnpa.org/california/islandora/object/cali%3A885 (accessed December 20, 2023).