The man takes a sound idea — for example, re-instituting the Cold War practice of ensuring that immigrants don’t “advocate or publish ‘the economic, international, and governmental doctrines’” of the precise ideology we’re fighting — and turns it into an “ideological certification” that exactly no one (outside his circle of true believers) trusts him to create, much less to enforce fairly and legally.

And he does it all with a tone that causes those who feel genuine and justifiable compassion for illegal immigrants peacefully working and raising families in this country to recoil at his obvious disdain. He does not communicate in the language of a leader making hard choices after balancing all the competing interests, but rather in the language of a man who’s punishing people he doesn’t like.

There is a powerful and, yes, compassionate argument for an immigration policy that is built around border security and domestic law enforcement. A president’s greatest priority is his citizens, and when there is powerful evidence that current immigration policy is harming the economic well-being and security of American families, there is an obligation to act.

In politics, however, method and message tend to merge, so a terrible messenger often discredits an otherwise-worthy message. On immigration, this is precisely what we see today. If present trends continue and Trump loses a winnable race in large part because he’s engaged in behavior that he should know repels the majority of the electorate, then the practical result will be not just the dreadful immigration policies of Hillary Clinton but also grave damage to the conservative case for immigration policies that protect and maintain American liberty, security, and prosperity.