A lot of populists after populism died just became socialists. At the beginning of the 20th century, socialism looked like it was going to take off. It didn't, of course, but a lot of people thought it was going to. ↗
Throughout the 20th century, the Republican Party benefited from a non-interventionist foreign policy. Think of how Eisenhower came in to stop the Korean War. Think of how Nixon was elected to stop the mess in Vietnam. ↗
I mean, certainly it's the single biggest event, I think, in terms of popular entertainment, or art even, if you say that, of the 20th Century. It's been film. It's the 20th Century's real art form. ↗