A few years ago I was preparing to write a magazine profile of Rodrigo Duterte, who had then recently been elected as president of the Philippines, when I came across “The White Man’s Burden,” Rudyard Kipling’s famous ode to imperialism, in a history book. I had never seen the full title before: “The White Man’s Burden: The United States and the Philippine Islands.” I had always thought it was a racist relic of the British empire! But no, Kipling wrote it after the U.S. won the Philippines from the Spanish in the Spanish-American War in 1898. The victory had announced America as a world power to be reckoned with, complete with overseas colonies. Kipling was posing himself as an emissary from the older and wiser imperial power with advice for the upstart on how to deal with their new brown people: “Take up the White Man’s burden — / Send forth the best ye breed — / Go bind your sons to exile / To serve your captives’ need.”

Only an American such as myself could be so totally oblivious to their own country’s imperial past. “One of the truly distinctive features of the United States’ empire is how persistently ignored it has been,” the historian Daniel Immerwahr writes in his introduction to How to Hide an Empire: A History of the Greater United States, his new book on the United States’ overseas empire. Triumphalist accounts of the U.S.’s rise to superpower status usually begin with World War II: Pearl Harbor roused the sleeping giant to save the world from fascism. But if the United States had been sleeping, it was only a brief nap after a vigorous workout. From the early 19th century through the 20th, the U.S. assembled a sprawling overseas empire, which grew to include the Philippines, Puerto Rico, Guam, Hawaii, Alaska, the Panama Canal Zone, the U.S. Virgin Islands, and American Samoa, comprising millions of colonial subjects. This story resists a happy moral arc.

U.S. imperial rule was defined at various times by neglect, patronizing racism, and brutal military campaigns. As Immerwhar writes, people in the territories were “shot, shelled, starved, interned, dispossessed, tortured, and experimented on. What they haven’t been, by and large, is seen.” He aims to correct this state of affairs by telling U.S. history from the point of view of the territories. While many commentators on U.S. empire have sought to shock Americans out of what the historian Niall Ferguson has called America’s “imperial denial” by focusing searing attention on its misdeeds, Immerwahr’s book is not primarily an exposé. He often deploys the good-natured quirkiness of a TED-talker; the book is full of pop-culture references and interesting anecdotes that challenge common sense. Immerwahr’s point is not to condemn empire but to explain it. And by doing so, he helps us better understand American foreign and military policy in the present — and the future.

The founders imagined the U.S. as an empire, despite the country’s revolutionary beginnings. “I am persuaded no constitution was ever before so well calculated as ours for extensive empire and self government,” wrote Thomas Jefferson. The country expanded by acquiring territories, which were ruled by the federal government with absolute authority, much like colonies. The residents of these territories — Native Americans, Catholics, free blacks, and unruly squatters — were seen as an alien threat to the white, Protestant utopia the founders hoped to create. The idea was for the government to orchestrate the orderly settlement of the territories before they became states, but this plan, in Immerwhar’s telling, was overwhelmed by rapid population growth, which sent settlers surging over the Appalachian Mountains in the mid-1800s. As settlers literally raced for land on horseback at the shot of a pistol, the native people who already lived there were driven into ever smaller territories and reservations.

Continental expansion provided material and ideological justification for overseas expansion. In order to feed the still-booming population on the continent, the U.S. annexed its first overseas territories in 1857: a few hundred tiny islands covered in guano, a valuable source of fertilizer at the time. At the same time, the settling of the American west led to the romanticization of the frontier. Where the founders had fretted over early settlers, afraid they might start wars with the native peoples or infringe on property rights (George Washington held considerable land in the territories), the frontiersman Daniel Boone was rescued from obscurity and made into a national hero by the mid-19th century. In the late 1800s, the historian Frederick Jackson Turner famously argued that the struggle to settle the frontier had shaped the national character into one of resourceful individualism, which laid the groundwork for American democracy itself.

One person who caught frontier fever was the young Theodore Roosevelt. Roosevelt was East Coast royalty, but spent much of his youth gallivanting out west, building a myth of himself as a frontiersman by writing books with titles like Hunting Trips of a Ranchman. Roosevelt was also an insatiable warmonger who crowed that “the most ultimately righteous of all wars is a war with savages.” A photo included in Immerwahr’s book of a 20-something Roosevelt posing stiffly in a buckskin suit with his hands gripped around a rifle suggests his obsession with belligerent manliness may have been a form of overcompensation. (“Give a sissy a gun and he will kill everything in sight,” is what Gore Vidal once wrote of Roosevelt.) By the 1890s, the frontier had been closed on the continent, but Roosevelt was in luck, for the fading Spanish empire was in the process of brutally suppressing a rebellion in Cuba which, along with the sinking of the USS Maine, served as the pretext for the Spanish-American war.

With the victory over the Spanish in 1898, and the subsequent acquisition of the Philippines, Puerto Rico, and Guam, the colonies took the place of the western frontier as the blank space on which to project American ambitions to shape a new world. The empire was memorialized in songs and books, while Americans hung redrawn maps on their walls and flocked to the “First Greater America Colonial Exposition” in Omaha, where a group of Filipinos thrilled the crowd with a rendition of “There’ll Be a Hot Time in the Old Town Tonight.” The famed architect Daniel Burnham, designer of the Flatiron Building, was commissioned to redesign Manila’s public spaces, and built an imperial complex in neoclassical style outside of the capital, modeling it after the hill stations where British colonizers cooled off in the summers.

Americans who shouldered the White Man’s Burden often took advantage of the colonies’ second-class status to carry out ambitious schemes free from regulations and public scrutiny on the mainland. American doctors and researchers used Puerto Rico as a giant laboratory in which ethics often fell by the wayside. One particularly egregious case Immerwhar brings to light is that of Dr. Cornelius P. Rhoads. Sent to Puerto Rico to help with a hookworm epidemic, he had to flee after it was revealed he’d written a letter to an American associate filled with racist vitriol, in which he seemingly confessed to murdering eight Puerto Ricans and “transplanting cancer into several more” to help bring about the genocide which, he wrote, would be the only way to save the island. While it was never proven that Rhoads actually killed anyone — he later claimed he was joking — it still seems a bit odd that Rhoads had a prestigious oncology award at Sloan-Kettering named after him until 2003.

The triumphant mood changed quickly after 1898. Although the U.S. had easily defeated the Spanish, it was soon bogged down in a war against its former ally in the Philippines, the nationalist Emilio Aguinaldo, who had been led to believe that he would be recognized as the leader of a newly independent nation after helping America defeat Spain. Unfortunately for Aguinaldo, when an ambivalent President William McKinley asked God what to do with the islands, the big guy told him to keep them, and to “educate the Filipinos, and uplift and civilize and Christianize them,” as McKinley recounted in a speech. Aguinaldo turned on his new imperial master.

The Philippine–American war was waged through the same erratic strategy of wanton violence plus ham-fisted attempts to make nice with the natives that would define future counterinsurgency campaigns. When they weren’t building roads or improving sanitation, U.S. soldiers burned farmland to the ground, waterboarded prisoners, and rounded up villages suspected of harboring insurgents in “reconcentration camps.” The war is estimated to have killed 4,196 U.S. troops and 775,000 Filipinos, a staggeringly lopsided body count which betrays the American tendency to visit mass destruction on civilians and combatants alike.

After insurgents killed 45 U.S. troops in an ambush in the town of Balangiga, on the southern island of Samar, American soldiers rampaged through the countryside, burning rice and buildings in revenge. “The interior of Samar must be made a howling wilderness,” said General Jacob H. Smith of the occupying forces. “I want no prisoners. I wish you to kill and burn, the more you kill and burn the better you will please me.” The atrocities sparked outrage at home, fueling a growing anti-imperialist movement. A century before the Iraq War awakened many Americans to the hypocrisy of conquering a people in order to free them, Mark Twain exposed the contradiction in biting commentaries. “There must be two Americas,” he wrote, “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.”

Today, the Philippine–American War has largely been forgotten. Reading about it, I wondered why it is not remembered better among the many other instances in which American values were starkly undermined by the actual conduct of Americans working in their name. A year before the controversy around the Confederate monument in Charlottesville erupted into a national firestorm, the return of six bells looted by U.S. soldiers from Balangiga barely warranted a mention in the press. The memory of the Philippine–American War is not so forgotten in the Philippines, where a recent blockbuster biopic of the young Filipino general Antonio Luna portrayed his American adversaries as “pompous xenophobes,” according to one review. Perhaps the election of Duterte, whose flagrant disregard for human rights and rabid anti-Americanism has bewildered many observers in the U.S., is a resurfacing of the Philippines’ traumatic colonial past.

Why are so few Americans aware of this history? How to Hide an Empire shows that many of the events that happened in the colonies are not remembered today because they were not deemed important at the time by the people who told memorable stories. This might seem like common sense, but the way we talk about historical “amnesia” suggests a past in which the facts were clear. At its best, Immerwahr’s book describes not only a forgotten history but a history of forgetting itself, as when Franklin Roosevelt removed prominent mention of a simultaneous Japanese attack on the Philippines from his famous address to congress after Pearl Harbor. As Immerwahr points out, FDR likely made the calculation that Americans wouldn’t care as much about this island nation halfway across the world, compared to the one that was closer and more culturally aligned.

American imperial history was further suppressed during the Cold War, when the idea that the U.S. might be anything but a champion of democracy was almost solely propagated domestically by leftist critics of U.S. foreign policy. It was not hard for many people to imagine empire-building as a brief and unimportant blip in the history of the country. After all, the formal empire was largely dissolved after World War II, as part of the wider move toward decolonization among the developing world. Alaska and Hawaii became states. Puerto Rico gained semi-autonomy as a commonwealth. The Philippines, which had been occupied by the Japanese and suffered horrific destruction, gained independence.

Yet, in Immerwahr’s telling, America’s empire did not disappear — it transformed. The U.S. “reshuffled its imperial portfolio” from large swaths of land to a string of military bases around the world, many of which are located in former imperial holdings. The U.S. became what he calls a “pointillist empire,” where military power is projected across the globe from hundreds of small patches of land. For Immerwahr, this transformation poses the puzzling question of why, at the height of its power, the U.S. decided to divest itself of all but a scattering of its territorial holdings. He argues that the rise of the global anti-colonial movement abroad and the civil rights movement at home made ruling imperial subjects politically impossible. At the same time, a series of innovations largely spearheaded by the U.S. military during World War II made it possible to reap many of the benefits of empire without undertaking colonization. These “empire-killing technologies” included advancements in communications, logistics, synthetics, and transportation which allowed U.S. troops and commerce to flow across the world as if it was all occupied territory.

In Immerwahr’s telling, these technologies helped bring about a world where globalization replaced colonization as “the great coordinating process.” Market dominance replaced military might as the crux of American power. The U.S. came out on top because economic and technological advantages gained in World War II allowed it to outcompete other countries. He gives the example of how American dominance of the airline industry led to the virus-like spread of English throughout the world via the vector of international air traffic controllers. As the book nears the present day, Immerwahr narrates a number of interesting stories from far-flung U.S. military installations (did you know the Beatles were inspired by music they heard from U.S. troops stationed in Liverpool?), but the reader becomes increasingly curious about why, in an era of increasingly seamless globalization, the U.S. stationed troops, planes, and ships all around the world in the first place. Immerwahr’s hyperfocus on territory physically controlled by the U.S., which was so crucial in the first half of the 20th century, begins to seem myopic when he addresses the second.

The historian Alfred McCoy offers a more complete view in his short and clarifying recent book In the Shadows of the American Century. America maintained its network of military bases after World War II to fight the Cold War, something barely discussed in How to Hide an Empire. American military supremacy provided the backbone of the American-led post-war order of alliances, economic treaties, international governing bodies, and pliant leaders (often installed through clandestine activities or invasion) that the U.S. constructed in the name of defeating communism and making the world safe for democratic capitalism. Far from being made obsolete, American military might secured the conditions for the market-based globalization that Immerwahr suggests replaced it.

Still, stripping empire to its roots in the control of territory reveals how even as the nature of empire changes, the way in which it’s hidden remains much the same. In the fall of 1950, Puerto Rican nationalists staged a violent uprising to protest the continued U.S. rule of the territory. A pair of nationalists attempted to assassinate President Harry Truman while he was sleeping. While the surviving assailant railed against specific injustices of U.S. imperialism on the island, the New York Times dismissed the uprising as “one of those mad adventures that make no sense to outsiders.” Such obfuscation resembles the response to 9/11, when Osama Bin Laden’s long-standing resentment of America’s military presence in the Middle East was largely smothered by hyperpatriotic discourse in the U.S. that framed him solely as a madman who hated America “for our freedoms.” In both cases, the reality of empire was obscured to preserve what the historian William Appleman Williams once called America’s “grand illusion” that it might maintain a global empire, however informal, without fully confronting imperialism’s contradiction of America’s professed values of freedom and self-determination.

It shows, also, that the dilemma of empire is as pressing today as it was in Mark Twain’s time. Donald Trump has made a lot of noise about winding down wars and withdrawing from alliances, but, seen from the far reaches of the pointillist empire, all of it seems as hollow as most of the other noises that issue from his mouth. Trump has shown little inclination to dismantle the world-spanning military apparatus that underpins America’s (yes, increasingly shaky) global supremacy.

The administration’s latest budget features a $750 billion increase in military spending, much of which would presumably support the nearly 700 U.S. military installations maintained today. And Trump does not seem particularly reluctant to use American military power to dictate events abroad. He shockingly made the good decision to withdraw U.S. forces from the quagmire in Syria only to address the crisis in Venezuela with a reckless bellicosity that threatens to entangle those forces again. In his incessant hinting at military intervention in Venezuela, Trump brings to mind the arch-imperialist Teddy Roosevelt’s idea of “big-stick” diplomacy — though no one would accuse Trump of speaking softly. A military intervention in Venezuela in the name of democracy would be as hypocritical, and likely as disastrous, as the campaign in the Philippines that got Roosevelt so hot and bothered. Now is as good a time as ever to familiarize yourself with the history of U.S. imperialism, if only to remember what an asshole Teddy Roosevelt was.