An Easter Prayer Breakfast in the East Room of the White House. (Jim Young / Courtesy Reuters)

Until very recently, scholars theorized that the advent of modernity would inexorably lead to a less religious world. Simply put, modernization equaled secularization. In Europe, that assumption was common to the theories of Karl Marx, Max Weber, and Sigmund Freud. In the United States, too, social scientists with policymaking influence, among them Walt Rostow and Daniel Bell, predicted the inevitable decline of religion as modernity marched forward.

The world today disproves that thinking. In the rapidly industrializing BRIC countries, Brazilians, Russians, Indians, and Chinese are turning increasingly to religious faith. The same is true in some ultramodern nations that are changing under the pressures of globalization, such as South Korea and even constitutionally secular Turkey. Africa, which as a whole is making significant economic gains, is also home to some of the world's fastest-growing Christian and Muslim communities. When the people of the global South turn to religion, moreover, they are adopting some of the most intensely devout and pious faiths, such as Protestant evangelicalism, Pentecostalism, and conservative forms of Catholicism and Islam. Rather than disappearing, these supposedly premodern worldviews are thriving in our postmodern world.

At least in theory, the United States should be well poised to navigate a world of faith-based geopolitics. Its two most recent presidents, George W. Bush and Barack Obama, are by all accounts deeply religious and well versed in many of the tenets of Christianity. They have differed in their approaches to foreign policy, but both have made overt references to faith. In reacting to 9/11 and the crisis over Iraq, Bush portrayed the United States as a chosen nation. "We Americans have faith in ourselves, but not in ourselves alone," he said in his 2003 State of the Union address. "We do not know -- we do not claim to know all the ways of Providence, yet we can trust in them, placing our confidence in the loving God behind all of life and all of history. May He guide us now."

Obama has emphasized religion in similarly strong terms. He has described the United States as a Judeo-Christian country and said in February that the great reformers in U.S. history acted "because their faith and their values dictated it, and called for bold action, sometimes in the face of indifference, sometimes in the face of resistance." Religious ethics has implications for foreign policy, too: As Obama continued, "When I decide to stand up for foreign aid, or prevent atrocities in places like Uganda, or take on issues like human trafficking, it's not just about strengthening alliances or promoting democratic values or projecting American leadership around the world . . . It's also about the biblical call to care for the least of these, for the poor, for those at the margins of our society."

Strangely, however, neither Bush nor Obama has been particularly successful in harnessing religion's authority in support of the United States' diplomatic and strategic goals. Bush relied too much on the exceptionalist belief that the United States was uniquely virtuous. In doing so, he alienated those who did not share that vision. By contrast, Obama has not always matched his soaring rhetoric with action on the ground.

Many of Obama's most important foreign policy speeches have placed religion front and center. In several significant addresses in 2009, he used religious ideas and values to support the promotion of democracy, human rights, and the war on terror. In China, he declared that true democracy and social stability would not be possible without respecting "freedoms of expression and worship." Accepting the Nobel Peace Prize, he invoked Reinhold Niebuhr's theology of irony to warn that the United States would sometimes have to use armed force to bring about peace and justice in a sinful world. And most notably, in Cairo, he admonished the region's Muslims, Jews, and Christians that peace and prosperity would never come unless they learned to tolerate one another's faiths, saying, "Freedom in America is indivisible from the freedom to practice one's religion. . . . That is the spirit we need today. People in every country should be free to choose and live their faith based upon the persuasion of the mind and the heart and the soul." That was the way of peace.

Rhetoric is important, but direct action grounds real diplomacy. And on that front, the White House has not kept up with the issue. It took 18 months for Obama to appoint a director of the State Department's Office of International Religious Freedom, which monitors the extent to which other nations respect the religious liberty of their own citizens. He has also been slow to follow up the religious liberty objectives he laid out, most notably in his Cairo speech, for the Middle East.

But while faith is important, some caution is warranted. As diplomatic history shows, U.S. leaders must tread carefully on religious matters. Not everyone shares the United States' religious worldview, which has two basic components that do not always sit easily with each other: an exceptionalist conceit of the United States as God's chosen nation and an embrace of religious liberty historically grounded in the separation of church and state. In the past, when U.S. policymakers preached the former, they quickly ran into trouble, such as when President William McKinley justified the seizure of the Philippines in 1899 -- and the brutal war that followed -- in the name of Christian uplift. In a telling slip that did not augur well for the wars in Afghanistan and Iraq, George W. Bush similarly erred when he spoke of launching a "crusade" against Islamic fundamentalist terrorism shortly after 9/11.

Yet doing nothing comes at a cost. Administrations that neglected, underestimated, or sidelined religion found themselves blindsided. President John F. Kennedy's foreign policy, for example, never recovered from his ignorance of the Buddhist monks who upset the equilibrium of South Vietnam's politics. The Buddhist crisis, which erupted in May 1963 and continued for months, undermined the U.S.-backed regime of Ngo Dinh Diem. "How could this have happened? Who are these people? Why didn't we know about them before?" an exasperated Kennedy asked about the Buddhists -- who merely represented 90 percent of South Vietnam's population -- after the outbreak of their revolt. Diem, of course, was overthrown, and the resultant political instability led directly to the escalation and Americanization of the war in Vietnam. In the late 1970s, Jimmy Carter, another president who wanted to bleach politics of faith, similarly underestimated the rise of political Islam in Iran. For both Kennedy and Carter, the problem was not triumphalist religion but an unrealistic desire to view international relations through a purely secular lens.

In fact, U.S. presidents and policymakers have been most effective when they have argued that religious liberty is a fundamental -- indeed, foundational -- human right to be protected and promoted around the world, not only as a good in itself but as a way to safeguard U.S. national security. Consider the case of President Franklin D. Roosevelt. Several years before the Japanese attack on Pearl Harbor, Roosevelt wanted the United States to take a more proactive role in resisting Nazi Germany and imperial Japan. He did not call for outright military intervention, but as early as 1937, he identified Germany and Japan as threats to the United States.

Still, Roosevelt faced two obstacles: first, a predominantly isolationist U.S. public that was opposed to playing a world role; and second, the impression that neither Germany nor Japan seemed capable of mounting an attack, let alone an invasion, against the continental United States. To overcome both these obstacles, F.D.R. turned to the issue of religious liberty. Religion, he argued at the start of his 1939 State of the Union address, was the foundation of all civilization, because it provided the source of democratic politics; in turn, democracy made international peace possible. Without religious liberty, he said, there could be no democracy. And without democracy, there could be no world peace.

Roosevelt returned to this faith-based democratic peace theory countless times in the years before and after U.S. entry into the war, most notably in his 1941 State of Union, when he outlined the Four Freedoms (including freedom of worship). By portraying the Nazis as a menace to religious liberty -- and to all religions, not just Judaism -- he solved both his problems at one stroke: It enabled him to use a common language and imagery, familiar to almost all Americans, to explain the threat to a public wary of intervention. In an increasingly interconnected world, it allowed him to argue that the Nazis were a danger to U.S. national security because they threatened certain values that underpinned international openness and world order. By conflating U.S. interests and ideals, Roosevelt built a powerful case for an anti-Nazi policy that allowed him to extend lend-lease aid to United Kingdom and the Soviet Union and do battle with the German navy even before December 1941. Once the United States entered the war, religion was an important part of the ideology that spurred the United States to victory.

In a world defined in large part by the growth of global faith, Obama would be wise to do so as well. Democracy promotion is important, but it would be far more effective if tied explicitly to the spread of religious liberty. Just as countries are penalized, diplomatically and economically, for undemocratic practices or human rights abuses, so, too, should they be subject to pressure, and perhaps even sanctions, if they violate their citizens' freedom of religion. It is clear which direction today's modernizing states are heading. Now, it is just a matter of Washington adjusting the way it interacts with them, because being able to speak the language of faith has served the United States well in the past. Should the White House start practicing what it preaches, it will win the United States a very large, and very important, audience.

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  • ANDREW PRESTON is Senior Lecturer in History and a Fellow of Clare College at Cambridge University. He is the author, most recently, of Sword of the Spirit, Shield of Faith: Religion in American War and Diplomacy.
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