In a fascinating essay at Patheos, Dean Curry describes Malcolm Magee's argument in What the World Should Be that President Woodrow Wilson's foreign policy was decisively shaped by his Presbyterian Reformed theology.
It is well known that Woodrow Wilson was a foreign policy idealist and that his approach to it was moralistic. After all, it was Wilson who famously promised that America's participation in World War I would not be about selfish national interest—or realpolitik -- but about the altruism of making the world "safe for democracy." What is not well known about Wilson, and what Magee explains in fascinating detail, is how Wilson's personal and political worldview was profoundly shaped by Reformed Protestant theology. Challenging the prevailing historiography of Wilson that has all but ignored Wilson's theology, it is Magee's thesis that Wilson was a "Presbyterian in politics, a twentieth century John Knox, a Christian statesman whose overriding motivation was his determination to do God's work in a fallen world."