In the years after World War II, it became conventional wisdom that the economic harshness imposed by the Treaty of Versailles — and especially the humiliation of its “war guilt” clause — helped fuel the rise of Adolf Hitler. That interpretation owes much to John Maynard Keynes’s 1919 bestseller, “The Economic Consequences of the Peace,” which denounced the treaty as a “Carthaginian peace” that was intended to crush Germany and ended by ruining Europe. But later scholarship has been far less sympathetic to Keynes’s view. “Most historians of the Paris peace conference now take the view that, in economic terms,...