In America, some of the most (apparently) devout people behave in the most secular ways. This is not a new phenomenon—the great sociologist Will Herberg was one of the first to identify it in his classic book, Protestant-Catholic-Jew (1955). Polls in the 1950s already showed that Americans were overwhelmingly religious, but they often seemed to know little about the faith they affirmed.

Dwight Eisenhower, president for much of the 1950s, was one of the most paradoxical presidents we’ve ever had with regard to religion. He relished public expressions of American civil religion, signing bills to add “one nation under God” to the Pledge of Allegiance and to make “In God We Trust” the national motto. Eisenhower proclaimed that the American political tradition required “deeply held religious faith.” But he perplexingly added, “And I don’t care what it is!”

If we need deeply held religious faith, then doesn’t it matter what that faith is? His sentiment may seem odd, but Eisenhower’s strong belief in the need for religion, and cavalier attitude about the details of that religion, is an important precedent to our current situation. Today we have a president who seems to know little about his professed religion, but who insists that (among other things) we’re going to go back to saying “Merry Christmas.” For a variety of reasons, he draws his most fervent support from self-identified white evangelicals.

Herberg (who was Jewish) traced the seeming contradictions of American devotion and American secularism to the integral role that religion itself played in American society. In 1955, being American almost always meant being religious, but Americans’ faith often did not have deep roots in the Christian or Jewish tradition. Thus, “America seems to be at once the most religious and the most secular of nations,” Herberg wrote.

He did not think that most Americans were being hypocritical about their religious commitments, but Herberg still noted that “the religion which actually prevails among Americans today has lost much of its authentic Christian (or Jewish) content. . . . Americans think, feel, and act in terms quite obviously secularist at the very time that they exhibit every sign of a widespread religious revival. It is this secularism of a religious people, this religiousness in a secularist framework, that constitutes the problem posed by the contemporary religious situation.”

That brilliant formulation of the secular-religious American paradox makes the Trump phenomenon seem less odd. Americans have a penchant for turning everything into an expression of religious commitment, which sometimes means that nothing is a (substantive) expression of religious commitment. Thus, a political goal of “making America great again” can have religious overtones to many Americans.

In this strain of political sentiment, the fact that the president has such spotty personal integrity and can articulate so little about his own faith does not disqualify him from being used to advance the cause of true faith. If that faith is deeply connected to America, then making America great again becomes a way of living out our beliefs.

Republicans don’t have the market cornered on this blending of faith and politics. Bill Clinton and Barack Obama were good at articulating faith-infused politics for the Democrats. But committed Christians will see the terrible risks we run by turning politics into an expression of faith. If America’s greatness is a part of your theology, then your theology is historically aberrant.

Portions of this post are drawn from my forthcoming history of American religion, to be published by Zondervan.