Only he himself, if he starts kicking anchor babys into the Hudson River ...
That's the problem with far-right populists. They can only destroy themselves. The attacks by the mainstream and the Left only makes them stronger.
While Tender's recent shrillness has found us on opposite sides of many discussions recently, he's dead right here. People have got to stop thinking of Trump through the prism of a mainstream Republican or Conservative campaign, he's channeling European right-wing populism, so both the GOP and the media don't understand what's going on.
There are two things that kill these kinds of political movements off a) ignoring them, outrage and indignation from people who aren't them are this beast's key food source b) overreach and incompetence.
All normal rules about US politics need to be re-considered in this circumstance... he's gaffe-proof, his base LOVES it when he's impolite and impolitic, and he's making a bunch of angry, insecure white men feel good about their prejudices and insecurities. Political gold.