Donald Trump is the only candidate for the presidency calling for the screening of potential immigrants for willingness to accept and adapt to American values. In the din of the yelling about racism and Islamophobia, let's not forget that the notion that those who want to immigrate should be prepared to assimilate has been around for well over a century. Here's a quote from a letter written by US President Theodore Roosevelt to the American Defense Society in 1909.
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 man's becoming in very fact 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, and this excludes the red flag, which symbolizes all wars against liberty and civilization, just as much as it excludes any foreign flag of a nation to which we are hostile.... We have room for but one sole loyalty and that is a loyalty to the American people.
Source: "Taking Back America", the last chapter in War on the Middle Class, by Lou Dobbs (Viking Penguin, 2006). Read the entire book, if you can. In the decade since Mr Dobbs wrote, things have become even worse, but it's not yet too late to stop or even reverse the Islamization of the West.