In a 1915 speech to the Catholic group the Knights of Columbus. Roosevelt said:
- There is no room in this country for hyphenated Americanism... a hyphenated American is not an American at all. This is just as true of the man who puts "native" before the hyphen as of the man who puts German or Irish or English or French before the hyphen. Americanism is a matter of the spirit and of the soul. Our allegiance must be purely to the United States. We must unsparingly condemn any man who holds any other allegiance. But if he is heartily and singly loyal to this Republic, then no matter where he was born, he is just as good an American as any one else.
- The one absolutely certain way of bringing this nation to ruin, of preventing all possibility of its continuing to be a nation at all, would be to permit it to become a tangle of squabbling nationalities, an intricate knot of German-Americans, Irish-Americans, English-Americans, French-Americans, Scandinavian-Americans or Italian-Americans, each preserving its separate nationality, each at heart feeling more sympathy with Europeans of that nationality, than with the other citizens of the American Republic. The men who do not become Americans and nothing else are hyphenated Americans; and there ought to be no room for them in this country. The man who calls himself an American citizen and who yet shows by his actions that he is primarily the citizen of a foreign land, plays a thoroughly mischievous part in the life of our body politic. He has no place here; and the sooner he returns to the land to which he feels his real heart-allegiance, the better it will be for every good American. There is no such thing as a hyphenated American who is a good American. The only man who is a good American is the man who is an American and nothing else.
- For an American citizen to vote as a German-American, an Irish-American, or an English-American, is to be a traitor to American institutions; and those hyphenated Americans who terrorize American politicians by threats of the foreign vote are engaged in treason to the American Republic.