There are a good many Americans who talk about an American century in which America will dominate the world. They rightly point out that the United States is so powerful today that we should assume a moral leadership in the world…The trouble with those who advocate this policy is that they really do not confine themselves to moral leadership...In their hearts they want to force on these foreign peoples through use of American money, and even, perhaps, American arms, the policies which moral leadership is able to advance only through the sound strength of its principles and the force of its persuasion. I do not think this moral leadership ideal justifies our engaging in any preventive war…I do not believe any policy which has behind it the threat of military force is justified as part of the basic foreign policy of the United States except to defend the liberty of our own people.

–GOP US Senator Robert Taft, served in the US Senate from 1939 until 1951 and ended his career as Majority Leader. By the start of his third term in the Senate, Taft had been given the nickname “Mr. Republican”; he was the chief ideologue and spokesperson for the conservatism of the Republican Party of that era, and he was the acknowledged national leader of the GOP’s conservative faction.  (In 1957, a Senate committee chaired by John F. Kennedy named Taft as one of the five greatest senators in American history, along with Henry Clay, Daniel Webster, John Calhoun, and Robert La Follette.)