In the 45-minute “festival of narcissism” that was Donald Trump’s rambling presidential announcement, one particularly nasty passage proved him to be a menace to the Republican Party. It was the one about Mexican immigrants.

The U.S. has become a dumping ground for everybody else’s problems. [Applause] Thank you. It’s true, and these are the best and the finest. When Mexico sends its people, they’re not sending their best. They’re not sending you. They’re not sending you. They’re sending people that have lots of problems, and they’re bringing those problems with us. They’re bringing drugs. They’re bringing crime. They’re rapists. And some, I assume, are good people.

That plays well with many far-right Republican primary voters desperately clinging to an America that no longer exists. But such rhetoric is the death knell for the GOP — and the party knows it. The Republican autopsy of its thumping in the 2012 presidential elections was blunt in its self-assessment. “Asked to describe Republicans,” the report notes on page 8, “[focus group attendees] said that the Party is scary,’ ‘narrow minded,’ and ‘out of touch’ and that we were a Party of ‘stuffy old men.’ Sounds like Trump.

The document was also clear about what the GOP needed to do to appeal to Hispanic voters.

If Hispanic Americans perceive that a GOP nominee or candidate does not want them in the United States (i.e. self-deportation), they will not pay attention to our next sentence. It does not matter what  we say about education, jobs or the economy; if Hispanics think we do not want them here, they will close their ears to our policies.

Tea Party menace Dick Armey perhaps put it best of all. “You can’t call someone ugly and expect them to go to the prom with you,” he told the writers of the GOP autopsy. “We’ve chased the Hispanic voter out of his natural home.” Trump’s rhetoric guarantees they won’t return.

I’m going to go out on a limb and predict that Trump will not be the next president of the United States or even the GOP nominee. But his harsh rhetoric and the way his opponents respond (not well, I suspect) to the xenophobic zingers he will hurl on the debate stage will hobble the next Republican nominee’s effort to secure the keys to the White House.

Follow Jonathan on Twitter: @Capehartj