his summer, after a long delay due to the pandemic, I finally took a long-awaited vacation to Colorado. Having just finished browsing through A People’s Atlas of Nuclear Colorado, I was thrilled by the opportunity to see some of the featured nuclear sites up close. In retrospect, I thought and acted exactly as Yuki Miyamoto describes in her insightful essay on state-sponsored nuclear tourism: a tourist who takes pleasure in crossing the physical and conceptual boundaries between the “nuclear” and the “non-nuclear” world. When I visited the former Rocky Flats Plant, however, I saw nothing unusual or extraordinary. All I could see was a typical suburban landscape in the West that alternated between mixed-grass prairies and subdivision houses.

Figure 1: Candelas Housing Development, adjacent to Rocky Flats, Colorado. Photograph courtesy of Toshihiro Higuchi.

It did not take much time before I realized that I was looking in the wrong place all along. In following the nuclear fuel cycle in Colorado, a state which David Havlick aptly likens to a vertically integrated nuclear weapons corporation, the Atlas demonstrates that many of the key nuclear sites are located not on the earth’s surface but above and below. It is telling that the curated pathways begin with uranium deposits and end with nuclear waste sites. Between them, the Atlas takes us to a myriad of locations located above and beneath the ground: uranium mines; missile silos; fallout shelters; a nuclear command bunker inside Cheyenne Mountain; the sky over the U.S. Air Force Academy; and the space orbit where the Global Positioning System (GPS) satellites controlled from Schriever Air Force Base circle the Earth. The Atlas also meticulously documents how nuclear facilities and military bases built on the ground tend to leave subsoil and groundwater stubbornly contaminated even after “cleanup” following their closures. No wonder casual tourists like me can only scratch (literally) the surface of nuclear geographies.

The anticlimax to my nuclear tourism in Colorado confirmed and reinforced a key takeaway that I learned from the Atlas: the U.S. nuclear weapons apparatus derives its structure, properties, and effects from a novel assemblage of different layers of the Earth and its envelope. Here I am taking a cue from Nigel Clark, who has applied Gilles Deleuze and Felix Guattari’s theory of assemblage in exploring the mutually constitutive relationship between geological formations and political formations (Clark, 2017). For historians of U.S. foreign relations, like myself, the notion of air-atomic power as a composite of planetary strata offers a new way to interpret the changing modes of U.S. engagement in the world. The history of the U.S. empire is typically told as one of outward growth, beginning with continental conquest and transitioning to an overseas empire, and finally to a global superpower. In this linear account of U.S. expansion, air-atomic power is seen as one of the key technological developments that “replaced colonization with globalization” after World War II by making it possible for the United States to contain its adversaries and advance its interests around the world without relying on overseas colonies (Immerwahr, 2019: 18).

Far from being relegated to the margins, however, some continental U.S. states like Colorado have re-emerged as a key staging area for global ambitions thanks to their settler-colonial conditions: secure and unimpeded access to all the planetary strata that are necessary to bring about air-atomic power. As many entries in the Atlas point out, the U.S. government has recently renewed its bid to extend its sovereignty vertically in the form of the domestic uranium reserve and the Space Force. At the same time, the air-atomic assemblage tends to leave numerous but relatively small and obscure footprints on the surface, such as silo hatches, blast doors, abandoned mine shafts, and groundwater monitoring wells. As my visit to the former Rocky Flat site suggests, the recent realignment and closure of many major nuclear and military facilities has only accelerated the trend of superficial invisibility through remediation, redevelopment, or wildlife conversions. Such characteristics of the air-atomic assemblage in the continental U.S., then, contribute to the mythology of the American homeland as a place of innocence (Hoganson, 2019).

The vertical perspective to air-atomic power that I took away from the Atlas also helps me understand the shadow side of the nuclear fuel cycle. As Clark (2017) has pointed out, the assemblage theory highlights interactions between components as key to explaining the properties and dynamics of an assemblage. Likewise, we can see many of the health, safety, and environmental problems discussed in the Atlas as arising from the complex and interlocking movements of different planetary strata that bring about air-atomic power. In her beautiful essay about the radioactive contamination of the Colorado River basin, A Laurie Palmer observes that, like an actual river, the effects of radioactive materials released from uranium mines and nuclear facilities “move eerily forward and backward in time, and spatially in all directions as the river basin spreads out across a wide area.” Similarly, Michael Lehman painstakingly documents how atmospheric circulation patterns put Colorado “squarely in the band of heaviest global fallout during the era of atmospheric testing at the Nevada Test Site from 1951 to 1962.” Human activities hardly help, as Nareg Kuyumjian shows in his issue brief, “Transporting Nukes.” Even the proposed high-level nuclear waste repository deep under Yucca Mountain, which is supposed to be among the most geologically stable places in the United States, is subject to the long-term and uncertain motions of faults, aquifers, and many other tectonic and hydrologic systems. And some of the toxic materials released in the nuclear fuel cycle tend to accumulate in lands, bodies, and ecologies, eventually forming a geological layer as yet another material trace of the Anthropocene.

By revealing the air-atomic assemblage of planetary strata through the thoughtfully paired accounts of the nuclear fuel cycle and its intrinsic danger, A People’s Atlas of Nuclear Colorado successfully disrupts not only what the editors call “the positivist, technocratic version of this story” but also the binary of colonialism and globalism in explaining the history of the American empire. I hope that the Atlas will catalyze further inquiries into vertical geographies as a new dimension to the American empire in the air-atomic age.  


Clark N (2017) Politics of strata. Theory, Culture, and Society 34(2-3): 211-231.
Hoganson K (2019) The Heartland: An American History. New York: Penguin Press.
Immerwahr D (2019) How to Hide An Empire: A History of the Greater United States. New York: Picador.

Toshihiro Higuchi is Associate Professor of History at Georgetown University. He studies the international history of the nuclear age with a focus on its scientific, technological, and environmental aspects.