Carlos Barria / Reuters

This week, Donald Trump clarified the stakes in the midterm elections. Speaking on behalf of the Republican Party, he urged his followers to back its congressional candidates at the ballot box in a demagogic video. It opens on a demented murderer speaking Spanish in court and segues to footage of the caravan of Honduran migrants entering Mexico, portraying them as barbarian hordes at the gates.

No responsible political actor would select and juxtapose those video images. No charitable or exculpatory account of its intent is even plausible. It was a naked effort to stoke bigotry and exploit ethnic anxieties.

And no Republican Party message is more prominent.

If the GOP succeeds next week at the ballot box, politicians all over the country will conclude that they can advance their careers by vilifying minority groups, frightening voters predisposed to xenophobia, and dividing Americans. No incentive structure is more dangerous to a multiethnic nation. Politicians in other nations marshaling similar tactics have sparked sectarian violence, campaigns of ethnic cleansing, and civil war. Trump happens to preside over a country where such extreme outcomes are unlikely. But that does not change the character of his tactics or the moral obligation to stand against them.

I do not much like the Democratic Party. But I desperately want Republicans to conclude that the GOP harms rather than helps its prospects when it vilifies minorities, stokes the authoritarian impulses of its most frightened voters, and willfully divides Americans. Decisively defeating GOP candidates in the midterms is the surest way to send that message—while a Republican victory will encourage future campaign ads that even more closely resemble the work of D. W. Griffith.

Don’t be complicit in what Ayn Rand once called “the lowest, most crudely primitive form of collectivism.” If voters reject today’s Republican tactics, they can bring about a future where they offer a non-odious alternative. A Democratic rout is the likeliest path to a GOP that doesn’t weaken America by inducing us to fear and hate one another. A divided country benefits Trump, and that is the country he will bring about with his rhetoric—until decent Republicans thwart his machinations. It is time to yell, “Stop!”

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