This article was originally posted at Christianity Today.

A couple weeks before President Trump fired James Comey, we learned that the then-FBI director was an admirer of 20th century theologian Reinhold Niebuhr. Thanks to sleuthing by Gizmodo, we learned that Comey’s Twitter display name was named after the father of Christian realism and that he had written his college thesis juxtaposing Niebuhr and Jerry Falwell. A recent article at CT made a case for how Comey’s recent actions may have been influenced by the theologian:

A Christian has an obligation to seek justice, the theologian argued, and this means entering the political sphere because that is the realm where one can find the power necessary to establish whatever justice is possible in the world. Comey’s decision to work for the FBI can be understood as a way of fulfilling Niebuhr’s vision of Christianity as a defender of justice.

Comey’s not the only recent public figure influenced by the late theologian, whose admirers include people on the left and right, including Jimmy Carter, Barack Obama, John McCain, and David Brooks. But what shaped Niebuhr’s worldview?

“You really can’t understand Niebuhr’s political theology unless you appreciate the fact that his life was really bracketed by war,” said Joseph Loconte, a history professor at The King’s College in New York City.

Niebuhr was a young man during World War I and had come into his own as a “Christian Protestant public intellectual” just prior to World War II, a period in which he embraced pacifism and socialism. As totalitarian socialism and fascism took off in the 1930s, “what had become settled beliefs for him, now they’re being upended by the realities in which he finds himself,” Loconte said.

Niebuhr himself admitted that his ideas shifted not as the result of “study, but the pressure of world events,” Loconte said.

Loconte joined assistant editor Morgan Lee and editor in chief Mark Galli to discuss what Niebuhr’s theology does and does not justify, what America’s foreign policy decisions on Iraq and Syria look like through a Niebuhrian lens, and what happens when people with good intentions make decisions with unintended consequences.

Joseph Loconte is an associate professor of history at the King’s College in New York City and the author of A Hobbit, a Wardrobe, and a Great War: How J.R.R. Tolkien and C.S. Lewis Rediscovered Faith, Friendship, and Heroism in the Cataclysm of 1914-1918.