In February 2003, Al Jazeera broadcast an interview with Donald Rumsfeld, then George W. Bush’s secretary of defense. “Would it worry you,” the interviewer asked him, “if you go by force into Iraq that this might create the impression that the United States is becoming an imperial, colonial power?” Rumsfeld swatted away the question. “I’m sure that some people would say that,” he responded, “but it can’t be true because we’re not a colonial power. We’ve never been a colonial power.… That’s just not what the United States does. We never have and we never will.” In March, the United States invaded Iraq. By April, it was operating a government of occupation. By May, it had effectively placed a proconsul in charge of the country.

In the early years of the Iraq war, the idea of the United States as an imperial power was, for a moment, a subject of serious debate. Longstanding left-wing critics of empire like Noam Chomsky were now joined by conservative hawks such as Niall Ferguson in agreeing that the United States was an empire, though they differed deeply on whether this was a good thing. But both Rumsfeld and the journalist questioning him exhibited a kind of historical amnesia. Rumsfeld denies the possibility that the United States could ever be an empire; the journalist asks if it is in the process of becoming one. But what if it had been all along?

HOW TO HIDE AN EMPIRE: A HISTORY OF THE GREATER UNITED STATES by Daniel Immerwahr Farrar, Straus and Giroux, 528 pp., $30.00

That is the question Daniel Immerwahr pursues in How to Hide an Empire: A History of the Greater United States. “One of the truly distinctive features of the United States’ empire,” he observes, “is how persistently ignored it has been.” In order to address this historical amnesia, we must, he argues, consider the United States not as it is typically represented on the map—as the mainland United States with corners in Washington state, Maine, Florida, and Southern California—but as a collection of all of the territories in which the United States has exercised sovereignty. This “Greater United States” includes not only Puerto Rico, whose colonial status is at least widely recognized if not deeply considered, but also other territories ranging from rocks covered in bird excrement to the approximately 800 military bases that the United States still operates around the world. (Britain and France have 13 bases combined; Russia has nine.)

The book is written in 22 brisk chapters, full of lively characters, dollops of humor, and surprising facts. (Did you know that the U.S. greenback, for example, is modeled on the Philippine colonial currency, and not the other way around?) It entertains and means to do so. But its purpose is quite serious: to shift the way that people think about American history. Americans tend to see their country as a nation-state, not as an imperial power. As such, its global reach and influence are often invisible to its own citizens. So are the complex reactions that its actions around the world produce. Without an understanding of empire, Americans may see events elsewhere—a caravan of Central American migrants heading through Mexico, let’s say—as foreign threats, rather than as a consequence of the global distribution of power and violence, as something shaped by the history and politics of the United States.

Histories of U.S. empire often start in 1898 with the Spanish-American War, out of which the United States took control of Puerto Rico and the Philippines. But nearly since its founding, the United States had been in the process of expanding and debating how it would expand from 13 Eastern states across the continent. Early national elites were divided on how to apportion land for Native Americans and maintain peace between them and European settlers. Daniel Boone, for years taught to schoolchildren as a “pioneer,” was in his own time a criminal, who, by taking white settlers westward into Native American lands, risked involving the U.S. government in conflict. Thomas Jefferson’s original idea for the Louisiana Purchase was that it would primarily provide access to southern ports, and that much of the remaining land would be kept for Native Americans, along with free black people, Catholics, and others he judged unfit for citizenship.

But over the course of the nineteenth century, opportunities for profit pushed individuals and governments to seize more and more land. The white settlers’ beliefs about racial difference served to both justify this expansion and to limit it. New states applied for admission to the union: some successfully, others—like Lincoln, West Dakota, Deseret, Cimarron, Montezuma, and the majority-Indian Sequoyah—were rejected. After the U.S.-Mexico War of 1846 to 1848, the United States acquired not the populous central and southern zones but only the relatively sparsely populated northern territories of Mexico, partly because of racism. Representatives who opposed expansion for moral reasons were joined by those who opposed trying to incorporate large numbers of people they considered racially unfit for democratic government. Those new territories would become states decades later only when white rule could be assured.

An unexploded shell from the USS Charleston in the streets of Caloocan in the Philippines in 1898. Douglas White/Navel History and Heritage Command

But while racist thought shaped the country’s enlargement, commerce was never far from the discussion either. One particularly strong chapter in How to Hide an Empire deals with the “guano islands” scattered throughout the Pacific and the Caribbean. By the 1850s, guano had become a highly prized commodity. Intensive, industrialized agriculture required supplies of nitrogen fertilizer, which could be made from bird excrement. To this end, an 1856 law allowed any American citizen to “take peaceable possession” of any previously unclaimed island where they discovered guano deposits. In that simple manner, the territory would come to belong to the United States.

While territories that bordered the nation could eventually expect full statehood, the guano islands resembled traditional overseas colonies. Because the islands were unpopulated—apart from the birds—the workers who would toil among mountains of guano often had to be tricked and coerced into going there. In some places, business owners employed Native Hawaiians; in others they exploited African Americans, who labored in conditions resembling convict camps. An 1889 uprising by workers on Navassa Island, off the coast of Haiti, led to the deaths of five whites; President Benjamin Harrison commuted the death sentences of its leaders after an investigation revealed that the workers had no recourse to any government official. This position nevertheless reinforced the notion that the islands were part of the United States.

The years after 1898 usually are seen as a rupture in the history of U.S. empire, as the United States acquired more substantial overseas colonies. But it wasn’t the fact of expansion that was new—that had been ongoing throughout the nineteenth century. Nor was it the conflict with foreign nations and the conquest of territory—Native American communities were foreign nations and had suffered violence and displacement as a result. Nor, for that matter, was it the acquisition of territory outside of the mainland—as the guano islands show. What was different was that the United States had acquired overseas territories with substantial native populations understood as nonwhite.

At first, the United States carried out its conquests of Puerto Rico, Cuba, and the Philippines in the name of liberation from Spanish tyranny. But hopes for genuine self-rule among the people in those former Spanish colonies soon met the reality of U.S. occupation. Cuba gained technical independence but with compromised sovereignty, as the United States insisted on the right to intervene in its affairs and frequently did so. In the Philippines, pro-independence forces led by Emilio Aguinaldo suffered a brutal counterinsurgent campaign, which cast doubt on the efficacy, not to mention the morality, of U.S. policy. Mark Twain, who became the most prominent anti-imperialist in the mainland United States, imagined colonial subjects thinking: “There must be two Americas: one that sets the captive free, and one that takes a once-captive’s new freedom away from him, and picks a quarrel with him with nothing to found it on; then kills him to get his land.”

As Immerwahr puts it, the United States faced a trilemma. It could have at most two of the following three things: republicanism, white supremacy, or overseas expansion. It was republicanism that lost out. In a 1901 ruling, the SupremeCourt established that the Constitution did not fully apply to overseas territories. Their residents did not have the same rights as mainland Americans. Immerwahr details the many consequences of making these legal gray zones: counterinsurgency in the Philippines followed by colonial government; medical experimentation and sterilizations in Puerto Rico, and an economy arranged around exploiting its status as a tax haven; and Hawaii turned over to the military after Pearl Harbor. By the end of World War II, Immerwahr reckons, there were more people living in colonies and under U.S. occupation—including in Japan and the U.S. zones of Germany—than in the mainland.

This was a temporary condition. The third era in the history of U.S. empire, from the postwar period to the present, saw a retreat from formal occupation. The Philippines obtained independence in 1946; Alaska and Hawaii got full incorporation; Puerto Rico, Guam, and Samoa got civilian rule. But the United States was not necessarily acting out of altruism. The struggles of colonized people for independence, anti-Filipino sentiment in California, and America’s desire to claim the mantle of freedom in the Cold War conflict with the Soviet Union were all part of the picture. The United States was also strategically shedding the undesirable parts of its power: the obligation to maintain order, to support colonial administrations, and, from the racist point of view of many white Americans, the colonial ties that facilitated migration to the United States.

Instead, it now kept an empire of bases: signing a 99-year lease for land in the Philippines, keeping control of Vieques in Puerto Rico, Guantánamo in Cuba, Okinawa in Japan, and many hundreds of other locations. In an era of airplanes and wireless communication, territory was not required for dominance; indeed, it could be a source of friction. Immerwahr, borrowing a term from historian Bill Rankin, calls this new geography of power the “pointillist empire,” and others have called it an “archipelago.”

Immerwahr’s book will arrive as perhaps the most hotly anticipated release in American diplomatic history in some time, in part because of an unusual professional dispute: He debuted the arguments of this book in early 2016 in the Society for Historians of American Foreign Relations’ prestigious Bernath lecture; the text of his speech was published, as is customary, in the field’s leading journal, Diplomatic History. So far, so normal. What set tongues wagging was Diplomatic History ’s decision to publish, on the eve of the appearance of Immerwahr’s book, an article-length rebuttal to the Bernath lecture, written by Paul Kramer, a historian of the Philippines, and entitled “How Not to Write the History of Empire.” Since its appearance in September last year, the Immerwahr-Kramer affair has been one of the first subjects of conversation among historians in this field.

For an article in an academic publication, Kramer’s piece made an astonishingly personal attack. It accuses Immerwahr’s essay of “reflecting deep historical currents of nationalist arrogance and short-sightedness.” Kramer says that in Immerwahr’s account, the people of the colonies rarely appear and only count when they are part of empire; that the colonies matter to him only for the way they affect the history of the United States. Kramer also objects to Immerwahr’s claim that mainstream American history has not accounted for the imperial role of the United States. Who, Kramer asks, counts as mainstream? His article includes an eight-page bibliographic appendix, listing books and dissertations on the subject of American colonialism.

If How to Hide an Empire resembled the work described by Kramer’s critique, it would indeed be a problem. Yet as How to Hide an Empire makes clear, Immerwahr’s argument is mostly intended for a mass audience, who won’t likely be familiar with the large body of work on this subject. Its goal is to convince a reading public of the centrality of empire to U.S. history. To do this, it does anchor parts of the argument with familiar figures; it is written from the mainland out, rather than the colonies in. Making the opposite choice would also yield an interesting and valuable book, but it would be a different book. “The history of the United States is the history of empire” is the line that closes How to Hide an Empire, and that is the point. On this, Kramer and Immerwahr would surely agree, in spite of the sparks.

Kramer’s strongest argument is that writing a history of U.S. empire as a history of territory leaves out a great deal, since “most expressions of American global power in the twentieth century” do not involve the conquest of new lands. Generations of American political leaders and government officials have sought and successfully developed more informal mechanisms of control, from economic pressure to CIA intervention. Parts of How to Hide an Empire bear out this critique. Writing of the 1960s, by which time Alaska and Hawaii had become states and the only colonies that remained were the Virgin Islands, American Samoa, Guam and other parts of Micronesia, Immerwahr asks, “Where had [America’s] imperialist spirit gone?” But in a decade that saw major escalation of the war in Vietnam, the U.S. invasion of the Dominican Republic, and America’s encouragement of political violence in Brazil and Indonesia, it’s not hard to find the “imperialist spirit” at work.

Left to right: housing for American troops in Okinawa in 1957, and aircraft maintenance at a base in U.S.-occupied Okinawa, Japan, in 1951.John Dominis/The Life Picture Collection/Getty; Werner Bischof/Magnum Photos

Immerwahr’s response is that thinking about territory, and not just informal mechanisms of control, can lead to important insights. (This approach also has the potential to reach people who are not convinced that indirect control or influence is worth describing as “empire.”) Immerwahr explains, for example, that the United States was willing to retreat from formal colonial possession when it could substitute the gains of empire at home, whether through natural resources or new technology. Indeed, one reason why the United States did not acquire major overseas colonies in tropical zones, while other European powers did, is that the country is already so large that it passes through multiple climactic zones, could produce products like sugar domestically, and possessed abundant re-sources of strategic products such as oil. As the twentieth century moved onward, synthetic chemicals further reduced the need for access to tropical markets. World War II saw acute shortages of rubber, for example, which the United States had largely obtained from European colonies, now seized by Japan. FDR imposed a national speed limit of 35 miles per hour to save tires; but by the end of the war, synthetic rubber had solved the problem.

The size of the U.S. economy in the postwar era—it accounted for half of global economic output—allowed it to spread international standards and practices (the octagonal red stop sign is nearly universal), spread the use of English, and shape the global economy, all but guaranteeing the United States access to the resources it needed. The possibilities of chemical substitution had dramatically lessened fears that the country would run out of resources: Fibers could be replaced by nylon or polyester, and plastic proliferated throughout postwar consumer society. The major exception was oil, as U.S. demand began to exceed supply. It is a telling exception, for it is precisely for access to the lifeblood of the global economy that the United States has repeatedly been willing to transgress international law. Facing the oil crises of the 1970s, Henry Kissinger mused that the United States “may have to take some oil fields.” “I’m not saying we have to take over Saudi Arabia,” he remarked at a National Security Council meeting in January 1975. “How about Abu Dhabi, or Libya?”

Immerwahr convincingly argues that the United States looks less like an empire than its European counterparts did not because U.S. policy maintains any inherent commitment to anti-imperialism, but because its empire is disguised first as continuous territory and later by the development of substitutes for formal territorial control. The United States “replaced colonies with chemistry,” and partially “substituted technology for territory.” It is a powerful and illuminating economic argument. To this, I think it must be added that non-territorial mechanisms of control, from CIA interventions to the policies of the International Monetary Fund, were essential to building and maintaining U.S. power in the twentieth century. That power can’t be understood without the Marshall Plan, or America’s support for the removal of Prime Minister Mohammed Mossadegh in Iran in 1953 and of President Salvador Allende in Chile in 1973. These get little attention in a book with a focus on formal territory. The pointillist strategy is part of hiding an empire, but it is not the whole story.

Nevertheless, the book succeeds in its core goal: to recast American history as a history of the “Greater United States.” Immerwahr’s final chapter, for example, centers on the bin Laden family. Yemen-born Mohamed bin Laden became the Saudi government’s preferred builder in the 1950s and worked on many classified projects for the U.S. military before his death in a plane crash in 1967. One of his 54 children, Osama, embraced a radically anti-Western interpretation of Islam. His primary grievance, among a litany of complaints about Western culture and behavior, was the presence of U.S. troops on bases in Saudi Arabia, reopened after the first Gulf War. From Afghanistan, he planned the attacks of September 11, 2001, which killed thousands and baited the Bush administration into a conceptually endless War on Terror.

Two of the things that have characterized the War on Terror have been the use of torture, carried out in the legal gray zones of Guantánamo Bay and military bases throughout the world, and the use of drones launched from a similar list of locations. It has been a war both provoked by America’s empire of bases, and fought from them. It is typical of U.S. imperial history that someone like Donald Rumsfeld could deny the very existence of empire while authorizing brutality that depends on it. Immerwahr’s book deserves a wide audience, and it should find one. In making the contours of past power more visible, How to Hide an Empire may help make it possible to imagine future alternatives.

*This article has been updated to correct the date of the Navassa uprising.