Anti-Islam animus was elite-driven before World War II, not populist

Evidence

Prior to World War II, Islam was a distant threat. With Muslimmajority lands occupied by European powers, the US government’s interactions with them were limited to deploying ambassadors whose reports reified the Orientalist view that “history does not record a single instance of successful constitutional government in a country where the Mussulman religion is the state religion.” Although such derogatory portrayals circulated among the intellectual elite, the average American was preoccupied with more pressing domestic economic concerns in the first half of the twentieth century. — Sahar F. Aziz, The Racial Muslim, 608