Politics is an enduring feature of human life, but political parties are mortal. This week we watched the beginning of the end of one of the United States’ great, illustrious parties. The Republican Party, as we knew it, is dying.

The death of a party is not so unusual. Scholars divide U.S. history according to six distinct party systems, each responding to a particular political era. Sometimes parties retain their names but morph ideologically, like the Democratic Party, which went from being Southern, pro-slavery and pro-Jim Crow to the opposite. On other occasions, parties collapse entirely, as did the Whig Party in the mid-19th century, torn apart by divisions over slavery. (In fact, in an interesting parallel, the fall of the Whigs was hastened by the rise of a party called the Know-Nothings, dedicated to stopping what was then seen as uncontrolled immigration.) Whatever the form of the Republican Party’s collapse, it will be messy.

Sunday’s debate may have been the watershed moment. As many commentators and some of his own strategists noted, it was pretty obvious what Donald Trump needed to do — apologize, be contrite, and then strike broad themes of change, bringing back jobs and putting the nation first. Ideally, he would have reached out to women — the group of voters he desperately needs to win the election.

Instead, Trump did the opposite. He minimized his behavior as “locker-room banter,” accused Bill Clinton of much worse and paraded the former president’s accusers at a news conference. Since then, things have spiraled downward. Trump’s strange, self-defeating strategy has led to speculation that his real ambitions lie beyond the election, when he may set up a conservative media network to rival Fox News.

It’s quite possible. But in any event, what it means for the Republican Party is simple: Donald Trump is not going away. Many Republicans have nurtured a fantasy that their party has been briefly taken over by a strange historical aberration who will lose the election, and then somehow things will go back to normal. Trump has now made it clear that he will not go gently into the night.

House Speaker Paul Ryan (R-Wis.) told Republican lawmakers on Oct. 10 that he would no longer support presidential nominee Donald Trump—the start of a messy breakup that will go on through Election Day. (Peter Stevenson/The Washington Post)

In fact, he has declared war on the GOP establishment. His goal is surely to take over the Republican Party and remake it into a populist, protectionist, nationalist party, the kind that his Breitbart-oriented advisers have been dreaming about for years.

There will be a fight for the soul of what’s left of the Republican Party. We can see the battle lines. People such as House Speaker Paul D. Ryan (Wis.), backed by most serious conservative intellectuals, will try to restore the party to its Reaganesque ideology — with free markets, limited government, entitlement reform and an assertive foreign policy. Others, such as Trump’s running mate, Indiana Gov. Mike Pence, backed by Christian conservatives, will try to bridge divides and keep everyone in a big tent. But then there is Trump, who has — for now, at least — the crowds, the energy and a powerful message. Political scientist Justin Gest recently surveyed white Americans on whether they would support a party committed to “stopping mass immigration, providing American jobs to American workers, preserving America’s Christian heritage, and stopping the threat of Islam.” Sixty-five percent said yes.

The Republican establishment could have stopped Trump but instead surrendered to him months, perhaps years, ago. When they want to criticize opponents for being weak-kneed, Republicans often recall Neville Chamberlain and his policy of appeasing Adolf Hitler. And yet that is exactly the approach that the party’s senior leaders took with Trump — appeasing him in the hope that doing so would satisfy his appetites. They tolerated, excused and covered up for Trump as he began his political career with “birther” racism, launched his presidential campaign with anti-Mexican slurs and heightened it with anti-Muslim bigotry, and thrilled crowds with policies that would be unconstitutional or amount to war crimes — all while demeaning and objectifying women. Winston Churchill said of appeasers: “Each one hopes that if he feeds the crocodile enough, the crocodile will eat him last.”

Trump will lose the election. Forget his dismal polls last week. He has almost never been ahead of Hillary Clintons for a single week since they were both nominated. The major models predicting the election have only once or twice put his chances over 40 percent.

But Trump will not sit in loyal opposition to Clinton. He tells his legions that the election will be rigged. He says that the media are lying and that reporting cannot be believed. He warns that the country will be utterly destroyed if Clinton wins. He is fueling a toxic movement of protest and insurgency.

Trump will lose. And he will destroy the Republican Party. The frightening question is what he will do to the country in the process.

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