Over the past couple of weeks the man who was supposed to be the front-runner has made a series of attacks on the man who is. Strange to say, however, Mr. Bush hasn’t focused on what’s truly vicious and absurd — viciously absurd? — about Mr. Trump’s platform, his implicit racism and his insistence that he would somehow round up 11 million undocumented immigrants and remove them from our soil.

Instead, Mr. Bush has chosen to attack Mr. Trump as a false conservative, a proposition that is supposedly demonstrated by his deviations from current Republican economic orthodoxy: his willingness to raise taxes on the rich, his positive words about universal health care. And that tells you a lot about the dire state of the G.O.P. For the issues the Bush campaign is using to attack its unexpected nemesis are precisely the issues on which Mr. Trump happens to be right, and the Republican establishment has been proved utterly wrong.

Talk in G.O.P. Turns to a Stop Donald Trump Campaign

Yet after committing hundreds of millions of dollars to shape the Republican primary contest and groom a candidate who can retake the White House, the conservative donor class is finding that money — even in an era of super PACs and billion-dollar presidential campaigns — is a devalued currency in the blustery, post-policy campaign fashioned by Mr. Trump, driven not by seven-figure advertising campaigns but by Twitter feuds and unending free publicity.

.. Andy Sabin, a New York supporter of Jeb Bush, said the question of what to do about Mr. Trump had come up repeatedly on the Hamptons fund-raising circuit this summer, as what seemed like a summer romance by disenchanted conservatives blossomed into a full-blown insurgency.

.. The cost of an anti-Trump campaign would be daunting: Reshaping opinions about Mr. Trump, a candidate with universal name recognition and a knack for garnering free airtime and column inches, could cost as much as $20 million. A sustained campaign aimed at Fox News viewers could cost $2 million a week, one Republican consultant working for a rival candidate estimated, while a more targeted effort, aimed at Iowa caucus-goers later this fall, would require as much as $10 million.

.. Allies of Mr. Bush, arguing that Mr. Trump helps the former Florida governor by stealing voters and attention from other anti-establishment candidates, remark that perhaps donors to Senator Ted Cruz of Texas, or Gov. Scott Walker of Wisconsin, might take the lead in financing a Trump takedown.

Ronald Reagan, Heretic

If only the candidates were truthful to the man and his record. For the real Ronald Reagan — serial tax-raiser, illegal immigrant amnesty granter, deficit creator, abortion enabler, gun control supporter and peacenik — would never be allowed on the stage. The party has moved so far to the right from Reagan’s many centrist positions that the guy would be told to go find a home among the Democrats.

.. As president, Reagan signed a bill that granted amnesty to nearly three million people who were in this country illegally. And then he went a step further, acting on his own after signing the first bill, to extend amnesty to another 100,000 people.

.. Reagan raised taxes at least four times during his two terms in office, and 11 times by some readings of the record.

.. Yep, with Reagan the government-hater in charge, the size of the federal government grew to 5.3 million employees, and the federal debt nearly tripled, to $2.9 trillion. What’s more, he raised the debt ceiling — something modern Republicans are willing to shut down the whole shebang over — 18 times. Heretic!

.. But if you want to see an act of real consequence, turn to the abortion liberalization bill that Reagan signed as governor of California in 1967. Legal abortions in his state went from 518 a year to nearly a million over the next decade.

.. What’s happened to Republicans since then is similar to what Reagan once said about his earlier political affiliation — he didn’t leave the party, the party left him.

What Donald Trump Understands About Republicans

The Trump phenomenon arguably represents a culmination of the 50-plus-year transformation of the Republican Party.

That transformation was set in motion in 1964, when Barry Goldwater, the Republican presidential nominee, opposed the newly enacted Civil Rights Act. What remained of longstanding black support for the Republican Party disappeared overnight.

.. By 1981-82, in large part because of the enfranchisement of blacks after passage of the 1965 Voting Rights Act, Southern Democrats, once the hard-core backers of segregation, moved sharply to the left on racial issues. By 1982, Southern Democrats in the House voted 66 to 6 in favor of legislation strengthening the Voting Rights Act. In the Senate, every Democrat from the Confederate South voted for the legislation.

.. In January of that year, Bush promised to expend political capital to pass comprehensive immigration reform that included a path to legal status and, ultimately, to citizenship. The Republican controlled House instead passed the Border Protection, Anti-Terrorism and Illegal Immigration Control Act of 2005. That bill amounted to a direct repudiation of the Bush proposal; it included only anti-immigrant and tough border provisions. The bill passed the House with Republicans voting 203 to 36 in favor and Democrats opposed 164 to 17. The bill died in the Senate.

.. Trump’s vitriol expresses the degree to which the American debate over immigration has grown ugly, even hideous. At the same time, Trump’s followers are motivated, and enraged, by what they see as a breakdown of law and order and the erosion of norms and standards they believe should be upheld. They are frustrated by the poor performance of the public schools their children attend, by cities and suburbs they believe to be under siege, by a criminal justice system they perceive as dysfunctional, and by a government they view as incompetent.

.. Trump clearly finds this endeavor personally gratifying, even as his odds of winning the nomination remain slim. To his followers, the letdown of defeat could be brutal, leaving them stranded, without a candidate who can successfully capture the intensity of their beliefs.