TR said this in 1907:
"In the first place, we should insist that if the immigrant who comes
here in good faith becomes an American and assimilates himself to us,
he shall be treated on an exact equality with everyone else, for it is
an outrage to discriminate against any such man because of creed, or
birthplace, or origin. But this is predicated upon the person's
becoming in every facet an American, and nothing but an
American...There can be no divided allegiance here. Any man who says
he is an American, but something else also, isn't an American at all.
We have room for but one flag, the American flag... We have room for
but one language here, and that is the English language... and we have
room for but one sole loyalty and that is a loyalty to the American
people."