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The history of American opposition to immigration is to a large extent a history of racism, which was often promoted by powerful or influential people.

Calvin Coolidge wrote in 1921 that “Biological laws tell us that certain divergent people will not mix or blend.” Henry Cabot Lodge warned, in an 1896 speech on the Senate floor, that immigrants could devastate the “mental and moral qualities which make what we call our race” — and Theodore Roosevelt praised Lodge for “an A-1 speech.” Roosevelt also told a friend he was worried about the “multiplication” of “Finnegans, Hooligans, Antonios, Mandelbaums and Rabinskis.”

A New York Times editorial in the 1920s warned of “swarms of aliens,” while a Washington Post editorial referred to Italians as “degenerate spawn of the Asiatic hordes.” Cold Spring Harbor, the prestigious laboratory, gave scientific credence to racist nativism. The same book editor who published Ernest Hemingway and F. Scott Fitzgerald also oversaw a string of xenophobic books.