For the first time in 70 years, the American people have elected a president who disparages the policies, ideas, and institutions at the heart of postwar U.S. foreign policy. No one knows how the foreign policy of the Trump administration will take shape, or how the new president’s priorities and preferences will shift as he encounters the torrent of events and crises ahead. But not since Franklin Roosevelt’s administration has U.S. foreign policy witnessed debates this fundamental.

Since World War II, U.S. grand strategy has been shaped by two major schools of thought, both focused on achieving a stable international system with the United States at the center. Hamiltonians believed that it was in the American interest for the United States to replace the United Kingdom as “the gyroscope of world order,” in the words of President Woodrow Wilson’s adviser Edward House during World War I, putting the financial and security architecture in place for a reviving global economy after World War II—something that would both contain the Soviet Union and advance U.S. interests. When the Soviet Union fell, Hamiltonians responded by doubling down on the creation of a global liberal order, understood primarily in economic terms.

Wilsonians, meanwhile, also believed that the creation of a global liberal order was a vital U.S. interest, but they conceived of it in terms of values rather than economics. Seeing corrupt and authoritarian regimes abroad as a leading cause of conflict and violence, Wilsonians sought peace through the promotion of human rights, democratic governance, and the rule of law. In the later stages of the Cold War, one branch of this camp, liberal institutionalists, focused on the promotion of international institutions and ever-closer global integration, while another branch, neoconservatives, believed that a liberal agenda could best be advanced through Washington’s unilateral efforts (or in voluntary conjunction with like-minded partners).

The disputes between and among these factions were intense and consequential, but they took place within a common commitment to a common project of global order. As that project came under increasing strain in recent decades, however, the unquestioned grip of the globalists on U.S. foreign policy thinking began to loosen. More nationalist, less globally minded voices began to be heard, and a public increasingly disenchanted with what it saw as the costly failures the global order-building project began to challenge what the foreign policy establishment was preaching. The Jeffersonian and Jacksonian schools of thought, prominent before World War II but out of favor during the heyday of the liberal order, have come back with a vengeance.

Jeffersonians, including today’s so-called realists, argue that reducing the United States’ global profile would reduce the costs and risks of foreign policy. They seek to define U.S. interests narrowly and advance them in the safest and most economical ways. Libertarians take this proposition to its limits and find allies among many on the left who oppose interventionism, want to cut military spending, and favor redeploying the government’s efforts and resources at home. Both Senator Rand Paul of Kentucky and Senator Ted Cruz of Texas seemed to think that they could surf the rising tide of Jeffersonian thinking during the Republican presidential primary. But Donald Trump sensed something that his political rivals failed to grasp: that the truly surging force in American politics wasn’t Jeffersonian minimalism. It was Jacksonian populist nationalism.

Celebrating Trump's victory outside the White House, November 9 2016 JOSHUA ROBERTS / REUTERS

IDENTITY POLITICS BITE BACK

The distinctively American populism Trump espouses is rooted in the thought and culture of the country’s first populist president, Andrew Jackson. For Jacksonians—who formed the core of Trump’s passionately supportive base—the United States is not a political entity created and defined by a set of intellectual propositions rooted in the Enlightenment and oriented toward the fulfillment of a universal mission. Rather, it is the nation-state of the American people, and its chief business lies at home. Jacksonians see American exceptionalism not as a function of the universal appeal of American ideas, or even as a function of a unique American vocation to transform the world, but rather as rooted in the country’s singular commitment to the equality and dignity of individual American citizens. The role of the U.S. government, Jacksonians believe, is to fulfill the country’s destiny by looking after the physical security and economic well-being of the American people in their national home—and to do that while interfering as little as possible with the individual freedom that makes the country unique.

Jacksonian populism is only intermittently concerned with foreign policy, and indeed it is only intermittently engaged with politics more generally. It took a particular combination of forces and trends to mobilize it this election cycle, and most of those were domestically focused. In seeking to explain the Jacksonian surge, commentators have looked to factors such as wage stagnation, the loss of good jobs for unskilled workers, the hollowing out of civic life, a rise in drug use—conditions many associate with life in blighted inner cities that have spread across much of the country. But this is a partial and incomplete view. Identity and culture have historically played a major role in American politics, and 2016 was no exception. Jacksonian America felt itself to be under siege, with its values under attack and its future under threat. Trump—flawed as many Jacksonians themselves believed him to be—seemed the only candidate willing to help fight for its survival.

Not since Franklin Roosevelt’s administration has U.S. foreign policy witnessed debates this fundamental.

For Jacksonian America, certain events galvanize intense interest and political engagement, however brief. One of these is war; when an enemy attacks, Jacksonians spring to the country’s defense. The most powerful driver of Jacksonian political engagement in domestic politics, similarly, is the perception that Jacksonians are being attacked by internal enemies, such as an elite cabal or immigrants from different backgrounds. Jacksonians worry about the U.S. government being taken over by malevolent forces bent on transforming the United States’ essential character. They are not obsessed with corruption, seeing it as an ineradicable part of politics. But they care deeply about what they see as perversion—when politicians try to use the government to oppress the people rather than protect them. And that is what many Jacksonians came to feel was happening in recent years, with powerful forces in the American elite, including the political establishments of both major parties, in cahoots against them.

Many Jacksonians came to believe that the American establishment was no longer reliably patriotic, with “patriotism” defined as an instinctive loyalty to the well-being and values of Jacksonian America. And they were not wholly wrong, by their lights. Many Americans with cosmopolitan sympathies see their main ethical imperative as working for the betterment of humanity in general. Jacksonians locate their moral community closer to home, in fellow citizens who share a common national bond. If the cosmopolitans see Jacksonians as backward and chauvinistic, Jacksonians return the favor by seeing the cosmopolitan elite as near treasonous—people who think it is morally questionable to put their own country, and its citizens, first.

Jacksonian distrust of elite patriotism has been increased by the country’s selective embrace of identity politics in recent decades. The contemporary American scene is filled with civic, political, and academic movements celebrating various ethnic, racial, gender, and religious identities. Elites have gradually welcomed demands for cultural recognition by African Americans, Hispanics, women, the LGBTQ community, Native Americans, Muslim Americans. Yet the situation is more complex for most Jacksonians, who don’t see themselves as fitting neatly into any of those categories.

Whites who organize around their specific European ethnic roots can do so with little pushback; Italian Americans and Irish Americans, for example, have long and storied traditions in the parade of American identity groups. But increasingly, those older ethnic identities have faded, and there are taboos against claiming a generic European American or white identity. Many white Americans thus find themselves in a society that talks constantly about the importance of identity, that values ethnic authenticity, that offers economic benefits and social advantages based on identity—for everybody but them. For Americans of mixed European background or for the millions who think of themselves simply as American, there are few acceptable ways to celebrate or even connect with one’s heritage.

Jacksonians see American exceptionalism not as a function of the universal appeal of American ideas, but as rooted in the country’s singular commitment to the equality and dignity of individual American citizens.

There are many reasons for this, rooted in a complex process of intellectual reflection over U.S. history, but the reasons don’t necessarily make intuitive sense to unemployed former factory workers and their families. The growing resistance among many white voters to what they call “political correctness” and a growing willingness to articulate their own sense of group identity can sometimes reflect racism, but they need not always do so. People constantly told that they are racist for thinking in positive terms about what they see as their identity, however, may decide that racist is what they are, and that they might as well make the best of it. The rise of the so-called alt-right is at least partly rooted in this dynamic.

The emergence of the Black Lives Matter movement and the scattered, sometimes violent expressions of anti-police sentiment displayed in recent years compounded the Jacksonians’ sense of cultural alienation, and again, not simply because of race. Jacksonians instinctively support the police, just as they instinctively support the military. Those on the frontlines protecting society sometimes make mistakes, in this view, but mistakes are inevitable in the heat of combat, or in the face of crime. It is unfair and even immoral, many Jacksonians believe, to ask soldiers or police officers to put their lives on the line and face great risks and stress, only to have their choices second-guessed by armchair critics. Protests that many Americans saw as a quest for justice, therefore, often struck Jacksonians as attacks on law enforcement and public order.

Gun control and immigration were two other issues that crystallized the perception among many voters that the political establishments of both parties had grown hostile to core national values. Non-Jacksonians often find it difficult to grasp the depth of the feelings these issues stir up and how proposals for gun control and immigration reform reinforce suspicions about elite control and cosmopolitanism.

The right to bear arms plays a unique and hallowed role in Jacksonian political culture, and many Jacksonians consider the Second Amendment to be the most important in the Constitution. These Americans see the right of revolution, enshrined in the Declaration of Independence, as the last resort of a free people to defend themselves against tyranny—and see that right as unenforceable without the possibility of bearing arms. They regard a family’s right to protect itself without reliance on the state, meanwhile, as not just a hypothetical ideal but a potential practical necessity—and something that elites don’t care about or even actively oppose. (Jacksonians have become increasingly concerned that Democrats and centrist Republicans will try to disarm them, which is one reason why mass shootings and subsequent calls for gun control spur spikes in gun sales, even as crime more generally has fallen.)

As for immigration, here, too, most non-Jacksonians misread the source and nature of Jacksonian concern. There has been much discussion about the impact of immigration on the wages of low-skilled workers and some talk about xenophobia and Islamophobia. But Jacksonians in 2016 saw immigration as part of a deliberate and conscious attempt to marginalize them in their own country. Hopeful talk among Democrats about an “emerging Democratic majority” based on a secular decline in the percentage of the voting population that is white was heard in Jacksonian America as support for a deliberate transformation of American demographics. When Jacksonians hear elites’ strong support for high levels of immigration and their seeming lack of concern about illegal immigration, they do not immediately think of their pocketbooks. They see an elite out to banish them from power—politically, culturally, demographically. The recent spate of dramatic random terrorist attacks, finally, fused the immigration and personal security issues into a single toxic whole.

In short, in November, many Americans voted their lack of confidence—not in a particular party but in the governing classes more generally and their associated global cosmopolitan ideology. Many Trump voters were less concerned with pushing a specific program than with stopping what appeared to be the inexorable movement of their country toward catastrophe.

Trump at a rally in Doral, Florida, October 2015 JOE SKIPPER / REUTERS

THE ROAD AHEAD

What all of this means for U.S. foreign policy remains to be seen. Many previous presidents have had to revise their ideas substantially after reaching the Oval Office; Trump may be no exception. Nor is it clear just what the results would be of trying to put his unorthodox policies into practice. (Jacksonians can become disappointed with failure and turn away from even former heroes they once embraced; this happened to President George W. Bush, and it could happen to Trump, too.)

At the moment, Jacksonians are skeptical about the United States’ policy of global engagement and liberal order building—but more from a lack of trust in the people shaping foreign policy than from a desire for a specific alternative vision. They oppose recent trade agreements not because they understand the details and consequences of those extremely complex agreements’ terms but because they have come to believe that the negotiators of those agreements did not necessarily have the United States’ interests at heart. Most Jacksonians are not foreign policy experts and do not ever expect to become experts. For them, leadership is necessarily a matter of trust. If they believe in a leader or a political movement, they are prepared to accept policies that seem counter-intuitive and difficult.

They no longer have such trust in the American establishment, and unless and until it can be restored, they will keep Washington on a short leash. To paraphrase what the neoconservative intellectual Irving Kristol wrote about Senator Joseph McCarthy in 1952, there is one thing that Jacksonians know about Trump—that he is unequivocally on their side. About their country’s elites, they feel they know no such thing. And their concerns are not all illegitimate, for the United States’ global order-building project is hardly flourishing.

The right to bear arms plays a unique and hallowed role in Jacksonian political culture.

Over the past quarter century, Western policymakers became infatuated with some dangerously oversimplified ideas. They believed capitalism had been tamed and would no longer generate economic, social, or political upheavals. They felt that illiberal ideologies and political emotions had been left in the historical dustbin and were believed only by “bitter” losers—people who “cling to guns or religion or antipathy toward people who aren’t like them . . . as a way to explain their frustrations,” as Barack Obama famously put it in 2008. Time and the normal processes of history would solve the problem; constructing a liberal world order was simply a matter of working out the details.

Given such views, many recent developments—from the 9/11 attacks and the war on terrorism to the financial crisis to the recent surge of angry nationalist populism on both sides of the Atlantic—came as a rude surprise. It is increasingly clear that globalization and automation have helped break up the socioeconomic model that undergirded postwar prosperity and domestic social peace, and that the next stage of capitalist development will challenge the very foundations of both the global liberal order and many of its national pillars.

In this new world disorder, the power of identity politics can no longer be denied. Western elites believed that in the twenty-first century, cosmopolitanism and globalism would triumph over atavism and tribal loyalties. They failed to understand the deep roots of identity politics in the human psyche and the necessity for those roots to find political expression in both foreign and domestic policy arenas. And they failed to understand that the very forces of economic and social development that cosmopolitanism and globalization fostered would generate turbulence and eventually resistance, as Gemeinschaft (community) fought back against the onrushing Gesellschaft (market society), in the classic terms sociologists favored a century ago.

The challenge for international politics in the days ahead is therefore less to complete the task of liberal world order building along conventional lines than to find a way to stop the liberal order’s erosion and reground the global system on a more sustainable basis. International order needs to rest not just on elite consensus and balances of power and policy but also on the free choices of national communities—communities that need to feel protected from the outside world as much as they want to benefit from engaging with it.