Naval War College and Harvard Extension School professor

Tom Nichols is a professor at the Naval War College and the Harvard Extension School and author of "The Death of Expertise." The views expressed here are his own.

Even as his overall approval ratings continue to erode, President Trump remains popular among a swath of Republican voters for whom he can do no wrong — including his endorsement of the now-vanquished Roy Moore, an accused child molester who nearly became a U.S. senator from Alabama.

This raises an important question: How should conservative critics of the administration approach those people who, a year in, remain unshakably attached to an administration plumbing such moral depths? Should we engage and try to understand these voters, or should we shame and scold in an effort to reawaken some moral sense in a party that once proclaimed itself the defender of patriotic and family values?

Personally, I am in the "shame and scold" camp. The "engage and understand" approach is based on the deeply flawed assumption that these voters don't know what they are doing. It is a kind of "root causes" explanation, in which Trump's supporters are good people who are merely expressing a yawp of anger at a globalized world that has left them behind.

This explanation, ironically, mirrors one that conservatives once rejected when liberals used it to explain crime in some poor minority communities decades ago. Conservatives refused to accept the mechanistic reasoning that human beings are no more than victims, passively responsive to their environment, when it was applied to behavior among African Americans. Yet now they embrace it to explain the astounding collapse of civic virtue among the white working class.

These voters are, indeed, angry. And their feelings are not entirely unreasonable: They fear — rightly — that much of the culture of political correctness is aimed at squelching their participation in public life. And, yes, they have legitimate concerns about globalization and changes that have both improved their standard of living and put many of them out of work.

But if these were really the issues at the bedrock of Trump's support, more of these voters would care about values and policy than actually do. The same people who blasted the Clintons — again, rightly — for sex, lies and elitist corruption are rallying behind a cast of characters in Washington who make the "swamps" of previous administrations look like experiments in good government. In their world, Michael Flynn is a hero and Robert S. Mueller III the enemy. The FBI is worse than the KGB.

None of this is rational, and it cannot be remedied with reasonable argument. These are the politics of resentment. Although inevitably poisonous, resentment feels good. It gives meaning to a life in turmoil. It allows voters to dismiss facts at will. It's a great rationale for staying put and staying mad. It gives focus to an otherwise inchoate rage. Why is your life less than you want it to be? It's all Don Lemon's fault.

The only response to such irrational and even hateful politics is to bypass pointless arguments and instead try to rouse a sense of basic decency. Are you arguing that black families were better off under slavery? Shame on you. Do you really believe America is no better than Russia? Shame on you.

The Alabama election, in particular, should suggest to Republicans that there's still a role for shame and, more important, that there might yet be a reservoir of virtue left in their party. Yes, turnout in the African American community helped defeat Moore. But the other side of the turnout equation was vitally important, as thousands of conservative voters echoed the moral revulsion of famous Alabamians such as Sen. Richard C. Shelby (R) and basketball great Charles Barkley by staying home or submitting a write-in ballot. Had all those write-in votes been cast for Moore instead, he'd be on his way to Washington.

Also noteworthy was the failure of former Trump adviser Stephen K. Bannon to turn the Moore campaign into some kind of experiment in the politics of working-class resentment. Bannon — inexplicably touting his Ivy League credentials in Alabama — was sent packing even as Moore was invoking God's will in refusing to concede. Conservatives should take heart that Bannon's incoherent stew of white nationalism and wacky economic populism did nothing to help Alabama conservatives overcome their misgivings about Moore.

Shaming and scolding, obviously, are not the only answer to our dysfunctional politics. Conservatives who oppose the politics of people such as Moore and Bannon will have to make a better case than disgust. Nonetheless, if sensible conservatives want to reclaim the GOP, they need to stop responding to small-minded, un-American resentments that have nothing to do with politics or government and everything to do with crackpot notions of social revenge. They can begin by returning three important words to our national lexicon: Shame on you.