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. ↗
Just as it had taken centuries to determine the true nature of the universe, so also the search for the beginning of human life proceeded well into the 20th century. ↗
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. ↗