The great Republican crackup has begun.

There is a growing group of Donald Trump partisans, including former House speaker Newt Gingrich, Rush Limbaugh and New Jersey Gov. Chris Christie. Then there are Republican officials who publicly support Trump and privately hope he will lose in November — a group that could only be counted via lie detector, but I would test Senate Majority Leader Mitch McConnell first. And there are Trump opponents and skeptics, including the 41st president, the 43rd president, Jeb Bush, Mitt Romney, Sen. Ben Sasse of Nebraska and House Speaker Paul D. Ryan. Ryan, in particular, is providing air cover for the unconvinced.

What common views or traits unite the most visible Trump partisans? A group including Limbaugh and Christie is not defined primarily by ideology. Rather, the Trumpians share a disdain for “country-club” Republicans (though former House speaker John Boehner apparently likes Trump because they were golfing buddies). They tend to be white and middle-aged. They are filled with resentment.

Above all, they detest weakness in themselves and others. The country, in their view, has grown soft and feeble. Their opponents are losers, lacking in energy. Rather than despising bullying — as Ryan, Romney and all the Bushes do — they elevate it. The strong must take power, defy political correctness, humiliate and defeat their opponents, and reverse the nation’s slide toward mediocrity.

There have always been politicians who despise weakness and the weak. Richard Nixon and Lyndon Johnson are examples. They were not always bad at governing, but they were bad human beings who came to a bad end.

Speaker Paul Ryan has backed away from his pledge to support whoever becomes the nominee, saying he's "not ready" to endorse Republican presidential candidate Donald Trump. Other GOP heavyweights, including the Bushes, are also not giving endorsements. (Jenny Starrs/The Washington Post)

This type of leadership can motivate, usually through resentment and anger. What it cannot do is inspire. Inspiring leaders are often those who identify with the weak. They may develop this trait by rising from poverty themselves, like Abraham Lincoln did. Or they may have had their capacity for empathy expanded by suffering, such as Franklin Roosevelt’s struggle with polio. In American history, inspiring leadership has often been informed by religion, which (at its best) universalizes our empathy.

This is the main reason that some of us cannot simply lump it and reluctantly lend our support to Trump. The Republican Party is not engaged in a policy argument; it is debating the purpose of politics. For some Trump opponents, the justice of a political system is determined by its treatment of the vulnerable and weak. In the Catholic tradition, this is called “solidarity.” Whatever you call it, this commitment is inconsistent with a type of politics that beats up on the vulnerable and weak — say, undocumented workers, or Muslims — for political gain.

Those who accuse Trump opponents of elitism are engaged in a particularly mendacious slur. Trump is attempting to place nativism at the center of U.S. politics. Those who resist are not enforcing the rules of a private club. Many — including religious people in poor and working-class communities — are defending a vision of politics in which empathy is honored and the weak are placed first. They are opposing a candidate who mocks disabled people, demeans women, engages in ethnic stereotyping and encourages religious bigotry.

Those who regard this tawdry mix of vulgarity and cruelty as typical of any social class are engaged in a particularly offensive form of condescension. Hating losers and the weak is fundamentally inconsistent with Christian ethics, and other sources of moral judgment, in every income quintile.

Make no mistake. Those who support Trump, no matter how reluctantly, have crossed a moral boundary. They are standing with a leader who encourages prejudice and despises the weak. They are aiding the transformation of a party formed by Lincoln’s blazing vision of equality into a party of white resentment. Those who find this one of the normal, everyday compromises of politics have truly lost their way.

This is not even to mention Trump’s pledge to limit press freedom, or his malicious birtherism, or his dangerous vaccine skepticism, or his economic plans that would bring global recession, or his lack of relevant qualifications, or his temperament of brooding and bragging, egotism and self-pity, or his promise to emancipate the world from American leadership, or his accusation that Ted Cruz’s father was somehow involved with Lee Harvey Freaking Oswald.

Some are trying their best to act as though all this were normal. But we are seeing, in the words of G.K. Chesterton, “lunacy dancing in high places.” None of this requires a vote for Hillary Clinton. But it forbids a vote for Donald Trump.

House Speaker Paul Ryan says he cannot support Donald Trump. Trump says he doesn't care. Can the two work out their differences? (Deirdra O'Regan/The Washington Post)

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