The necessary and compelling reason to vote for President Trump in 2016, for many white evangelicals and other conservative Republicans, was the Supreme Court. That reason is now gone.

Or it will be soon, if Republican senators can manage to avoid COVID-19 infections long enough to confirm Amy Coney Barrett's nomination. Hearings on her candidacy begin Monday, and the subsequent vote now enjoys plurality support. Her confirmation can and probably will be done before Election Day, at which point Trump's SCOTUS voters can — and, on this very basis, should — dump him as swiftly and mercilessly as he'd dump them were they no longer politically useful.

The Supreme Court vote for Trump was never a good rationale for backing him in the 2016 GOP primary, because every other candidate would have produced a very similar SCOTUS nomination shortlist. But once Trump was the party's chosen champion against Democrat Hillary Clinton, the certainty that the next president would fill at least one seat (replacing the late Justice Antonin Scalia) made the Supreme Court, in the words of pundit Hugh Hewitt, "Trump's trump card on the #NeverTrumpers."

A "very liberal SCOTUS means ... conservatism is done," Hewitt argued in a representative case for Trump. "It cannot survive a strong-willed liberal majority on the Supreme Court. Every issue, EVERY issue, will end up there, and the legislatures' judgments will matter not a bit." Thus did SCOTUS voters who were otherwise critical of Trump describe backing him anyway on exactly this transactional logic: He would steer the Supreme Court in a better direction than Clinton would, and that was what mattered most.

I was skeptical Trump would deliver the sort of nominee(s) conservative SCOTUS voters wanted, because his personal philosophy of constitutional interpretation — if we should even dignify it with that label — is nothing like the small-government originalism or textualism they favor. But I was wrong. Trump seems to have heeded the Republican establishment here. He's turned out three nominations very pleasing to this portion of his base: Justice Neil Gorsuch for those with a libertarian edge, Justice Brett Kavanaugh for the executive authoritarians and national security hawks, and now Barrett for the social conservatives (in terms of cultural cachet, at least; her actual bench record is more complex and shows a civil libertarianism that seems to place her between Kavanaugh and Gorsuch on this measure).

Once Barrett is confirmed, then, the transaction is complete. The SCOTUS voters got what they wanted (a 6-3 conservative majority on the Supreme Court), and Trump got what he wanted (the presidency). The deal is done.

And given that fact, why should SCOTUS voters support Trump again in 2020? They don't owe him anything. They paid in full in 2016, and now he's held up his side of the bargain, too. What else is there to say? You don't hang out with the car salesman after you've signed the papers. You certainly don't pay him twice the sticker price for providing precisely what he promised. This is how a transaction works, and the Trump-SCOTUS voter transaction is over. Electing him again won't make Gorsuch, Kavanaugh, and Barrett somehow more confirmed to the Supreme Court than they already will be.

If anything, giving Trump a second term could backfire for conservative SCOTUS voters' goals. Justice Stephen Breyer, nominated by then-President Bill Clinton in 1994, is 82 years old and considered the court's second-strongest liberal. Were Breyer to die in the next four years, a still-President Trump could create a 7-2 conservative supermajority. This might sound like a further triumph for SCOTUS voters, but a fourth Trump nomination could well do their cause more harm than good.

The backlash would be intense. Court-packing and/or a serious loss of legitimacy for the Supreme Court would become all but inevitable. Democratic panic and partisan animus would escalate beyond its present heights. Centrist swing voters, alarmed by the sharp rightward bend of the most visible stem of the judicial branch, might attempt to restore balance in Washington by handing both congressional houses to Democrats in the 2022 midterms and rejecting comparative moderates like this year's Democratic nominee, Joe Biden, in the 2024 presidential primaries. The dream of a 7-2 conservative court could transform into the nightmare of a 9-7 liberal majority alongside Democratic control of Congress and the White House — the institutional version of Trump's radicalizing effect on the left.

A prudent temperance, then, is more likely than greedy overreach to secure the pending victory Barrett's confirmation signifies. Having gotten what they wanted from him, declining to re-elect Trump may be the best strategic move conservative SCOTUS voters can make. They should content themselves with the bird they have in hand — if they reach for more, they may find a viper in the bush.

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