Post editorial writer Quinta Jurecic says President Trump's reprehensible, and legal, pardon of former sheriff Joe Arpaio reveals weaknesses in the American system of government. (Gillian Brockell,Kate Woodsome/The Washington Post)

Repetition is the enemy of maintaining proper distinctions. It is a short road from being serially outraged to being slightly bored to being completely inured.

Thus many are likely to find the pardon of former Arizona county sheriff Joe Arpaio to be just another . . . something. Just another public feeding of President Trump’s base; or just an additional shiny distraction from real issues; or just one more cause for head-shaking and shoulder-shrugging; or just further evidence of the tawdry political company kept by the president of the United States.

This would be a mistake. This presidential action is not “just” anything. Following his expression of sympathy for the “very fine people” attending a white- supremacist rally in Charlottesville — who were, he said, defending “our history and heritage” — Trump must have known his next move would be highly symbolic, either as a retreat from prejudice or as its affirmation. What followed with the Arpaio pardon constitutes the most forthright racist incitement of the Trump era.

Trump has called Arpaio a “great American patriot,” employing a definition of patriotism that includes extreme ethnic profiling, terror raids, and cruel and unusual punishment. A definition of patriotism that covers using internment camps in extreme heat, parading women and juvenile offenders for the cameras in chain gangs, and degrading inmates in creative acts of bullying. This is not patriotism; it is the abuse of power in the cause of bigotry.

Others have commented on the legal precedent of effectively pardoning someone for abusing the constitutional rights of an ethnic minority. Done in a manner that employs the pardon power as a reward for political loyalty. Resulting from a process that evidently did not involve the normal review and recommendation of the Justice Department’s pardon attorney. Was White House Counsel Donald McGahn — a reputed libertarian — involved in this permission for swaggering government oppression? Better question: Why did he not resign in protest? And how about Gary Cohn, who famously almost resigned over events in Charlottesville, demanding that the president “must do better”? Does he think the Arpaio pardon is doing better?

President Trump pardoned former Maricopa County, Ariz., sheriff Joe Arpaio Aug. 25. Here’s what you need to know. (Patrick Martin,Victoria Walker/The Washington Post)

Congressional Republicans have often taken a wait-and-see attitude toward the dishonoring and destruction of their party. Now they can hardly deny that Trump’s worst moments are his most authentic moments, or that his definition of loyalty requires defending the indefensible. A few voices — including both Arizona senators and House Speaker Paul D. Ryan — were critical of the pardon. But congressional hearings demanding an account of the pardon’s purpose and process would demonstrate seriousness in the only task — the only path of self-respect and self-preservation — left to Republican leaders: attempting to salvage a party identity separate from racism.

These legal and political ramifications are clear enough. But it is the moral damage that is deepest: the stoking of tribal hatreds; the reckless fracturing of national unity; and the statement made about human worth.

A society’s treatment of prisoners is a measure of its commitment to human dignity. Some of these men and women are guilty only of the wrong geography in trying to feed their families. Others have done terrible things. But they are still — all of them — men and women, human beings, at the complete mercy of the state. According to Jewish and Christian teaching, they bear God’s image, which can never be completely effaced. Treating them humanely is the expression of a defining national belief: that human rights are not earned or granted, they are recognized. Or not.

Arpaio made a career of dehumanizing prisoners in his charge. His pardon sends the signal that some people are less than human. In one sense, this is perfectly consistent. Trump has employed dehumanization as a political tool from the start — of refugees, of migrants, of Muslims. By his pardon of Arpaio, he has metaphorically pardoned his own cruel and divisive approach to politics. It is a further step in Trump’s normalization and entrenchment of bigotry in our public life.

This creates a personal dilemma for many Republicans. How do they explain to their neighbors, and to their own children, their involvement with an institution that has been allied with forces of exclusion (at least at the national level)? The answer is not for all people with pricked consciences to leave, lest only unpricked consciences remain. But complacency is permission. Resistance is required. Any party that swallows the Trump/Arpaio ethic will be poisoned. And gagging, in this case, is a sign of health.

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Read more on this topic:

Jonathan H. Adler: Joe Arpaio is neither a conservative nor a hero

Robert Bauer: The Arpaio pardon could be a test run for shutting down the Russia investigation

Radley Balko: Trump considers pardoning Joe Arpaio, and gives racists a reassuring wink

Erik Wemple: ‘Fox & Friends’ guest: Former sheriff Arpaio deserves pardon, Medal of Freedom

The Post’s View: This would be a travesty of justice