By MICHAEL GERSON   

The presidential candidate who has consistently led the Republican field for four months, Donald Trump, has proposed: forcibly expel 11 million people from the country, requiring a massive apparatus of enforcement, courts and concentration camps; rewrite or reinterpret the 14th Amendment to end the Civil War-era Republican principle of birthright citizenship; build a 2,000-mile wall on our southern border while forcing Mexico to pay the cost. He has characterized undocumented Mexican immigrants as rapists and murderers, and opposed the speaking of Spanish in America.

Republican candidates have proposed: to favor the admission of Christian over Muslim refugees from the Middle East; to “send home” Syrian refugees, mainly women and children, into a war zone; to “strongly consider” the shutting down of suspicious mosques; to compile a database of Muslims and (perhaps) force them to carry special identification showing their religion. They have compared Syrian refugees to “rabid dogs,” ruled out the possibility of a Muslim president, and warned that Muslim immigration to America is really “colonization.”

There are, of course, Republican presidential hopefuls who have vigorously opposed each of these proposals, arguments and stereotypes. But Donald Trump has, so far, set the terms of the primary debate and dragged other candidates in the direction of ethnic and religious exclusion. One effect has been the legitimization of even more extreme views—signaling that it is OK to give voice to sentiments and attitudes that, in previous times, people would have been too embarrassed to share in public. So in Tennessee, the chairman of the state Legislature’s GOP caucus has called for the mobilization of the National Guard to round up Syrian refugees and put them in camps. Many Republicans are now on record saying that Islam is inherently violent and inconsistent with constitutional values (while often displaying an ironic and disturbing ignorance of those values).

Vin Weber, a prominent GOP strategist, told me that many Republicans remain in “denial mode” about the possibility of Trump’s nomination. “How can you be the leader in national polls,” Weber says, “and in the early states, and maybe even in money, and be counted out?” In spite of saturation media coverage, Weber thinks the Trump effect on the GOP is “understated.” The attention of commentators has often been focused on the horserace aspect of the campaign or on the narrative of insider vs. outsider, rather than on what Weber calls Trump’s “transformational message.”

That message comes in the context of a long period of political pessimism —more than 10 years in which polls have generally found more than 60 percent of Americans believing that their country is on the wrong track. There has been an angry decline in respect for most social institutions, including government. This has left some Americans more open to radical political answers—more prepared, in Weber’s words, “to roll the dice on the future of the country.”

“We’re going to have to do things,” says Trump with menacing vagueness, “that we never did before.” And if disrespect for institutions is common, Trump is its perfect vehicle—combining the snark of Twitter with the staged anger and grudges of reality television.

But in all this, it is easy to miss Trump’s policy ambition. He would spark trade wars with China and Mexico and scrap the world trading system—which Republicans have helped construct since World War II—replacing it with an older kind of mercantilism. He would make the seizure of Middle Eastern oil the centerpiece of his regional strategy—turning a spurious liberal charge into a foreign policy doctrine, and uniting the Arab world in rage and resentment.

And Trump would make, has already half-made, the GOP into an anti-immigrant party. Much of Trump’s appeal is reactionary. He has tapped into a sense that an older America is being lost. In a recent poll, 62 percent of Republicans reported feeling like “a stranger in their own country.” This is a protest against rapid and disorienting social change, against an increasingly multicultural country, and against the changes of the Obama years.

It does not take much political talent to turn this sense of cultural displacement into anti-immigrant resentment. Only a reckless disregard for the moral and political consequences.

As denial in the GOP fades, a question is laid upon the table: Is it possible, and morally permissible, for economic and foreign policy conservatives, and for Republicans motivated by their faith, to share a coalition with the advocates of an increasingly raw and repugnant nativism?

(Washington Post Writers Group)