When he was an undergraduate at William and Mary College, former FBI Director James Comey wrote his senior thesis, "The Christian in Politics," on the theologian Reinhold Niebuhr. Comey has said since that the Niebuhr's thought continues to influence him. Similar tributes to Niebuhr have come from Jimmy Carter, John McCain, and Barack Obama.

That Niebuhr still gets mentioned by public leaders is not surprising. He was immensely influential in public life himself, engaging actively in both state (New York) and national politics. He even had a direct line to the White House during the Kennedy years. During that period, his writings were popular with folks who were not particularly religious: the journalist Walter Lippman, for example, and the diplomat Dean Acheson. Indeed, the designation of Niebuhr as “the Twentieth Century’s greatest theologian,” actually came from the Harvard political historian, Arthur Schlesinger, Jr., who was not known for any sort of religious commitments.

Fuller Seminary recently screened Martin Doblmeier’s new documentary, “American Conscience: The Reinhold Niebuhr Story.” Those of us who have admired Doblmeier’s highly acclaimed 2003 film on Dietrich Bonhoeffer, the German theologian martyred in Hitler’s Germany, came with high expectations. We were not disappointed. The Niebuhr documentary is splendid. And we got to see it, not only with Doblmeier present to discuss it, but also with Hal Holbrook in the audience—he is Niebuhr’s voice in the film.

A number of present day theologians make their appearance in Doblmeier’s documentary, providing insightful commentary on Niebuhr’s life and thought. For me, it was like taking a refresher course on Niebuhr. His influence in the theological guild persists, but more often these days his name comes up in testimonies from the like of Comey and Obama.

One could argue that having an influence on public leaders more than on his theological colleagues was an intentional strategy on Niebuhr’s part. Martin Marty has pointed out that while Niebuhr never completely abandoned his role as a church-based theologian, he gradually became much more focused on the discussions of religion and public life that took place beyond the borders of the church community. This explains why, Marty observes, when Niebuhr was asked to name the greatest theologian in American history, his choice was Abraham Lincoln.

Not everyone in the scholarly community looked with favor on Niebuhr’s influence in the broad public arena. In my own evangelical world, Niebuhr’s “secular” reception has often been seen as a sign that he had undercut the essential supernatural grounding for theology. But the criticisms came from other quarters as well, as captured succinctly in a Harvard philosopher’s derisive reference to Niebuhr’s non-Christian admirers as “atheists for Niebuhr.”

I pretty much side with Niebuhr in all of this — at least in the kind of thing he was doing. I don’t know if Abraham Lincoln deserves to be ranked higher than, say, Jonathan Edwards in the pantheon of American theologians, but Lincoln did use theological categories to speak effectively to the nation’s soul in times of crisis. Lincoln’s views about our relationship to God may have been more deistic than traditionally Christian, but he certainly was right to talk about the need for both North and South to repent of the evils of racial injustice and warfare, and to urge prayers for a binding up of the nation’s moral and spiritual wounds. And my own assessment is that Barack Obama’s singing “Amazing Grace” at the Charleston memorial service was a marvelous act of presidential leadership.

The United States is not a theocracy. The role of religion in public life is a matter for ongoing discussion. Niebuhr understood that, and was willing to take some risks in thinking theologically alongside people of no particular religious convictions who nonetheless cared deeply about what many of us think of as the spiritual health of our collective lives as citizens.

The issues that Reinhold Niebuhr dedicated his career to exploring have not become less important in the public arena. For that reason, I would take it as a sign of hope if the present occupant of the White House announced that he had watched Martin Doblmeier’s new documentary and found Niebuhr to be “a really great guy — a terrific guy.” Trumpians for Niebuhr, anyone?