Judge Neil Gorsuch testifies on Capitol Hill. (Susan Walsh/Associated Press)

THE STANDOFF over Judge Neil Gorsuch’s Supreme Court nomination is the latest episode in a years-long cycle of political retribution that has diminished the Senate and harmed the country. It nevertheless represents a depressing new low. Senator after senator acknowledges that the body is about to make a historic mistake, setting precedent and changing procedures in a way that will, over time, erode the quality of both the Senate and the judiciary. But few seem interested in defusing the dispute.

Democrats are preparing to filibuster a well-qualified judge, marking the first time a partisan filibuster has been mounted against a high court nominee. In response, Republicans are preparing to change the rules and eliminate the filibuster on Supreme Court nominees, ending the minority party’s ability to demand meaningful consultation on presidential appointments to any major office (since Democrats, when they were in the majority, had already abolished the filibuster for other nominations). The Senate’s 52 Republicans cannot overcome a filibuster of Mr. Gorsuch without the help of eight Democrats. But they can permanently change Senate rules by simple majority vote.

“We’re headed to a world where you don’t need one person from the other side to pick a judge,” Sen. Lindsey O. Graham (R-S.C.) said. “The judges are going to be more ideological, not less.”

It would be better for everyone if the two sides struck a bargain that resulted in Mr. Gorsuch’s confirmation and preserved the filibuster for future nominees. But the trust required for an agreement on judicial nominees evaporated when Senate Majority Leader Mitch McConnell (R-Ky.) rallied Republicans last year to shut out Judge Merrick Garland, whom President Barack Obama named to fill the seat Mr. Gorsuch has now been tapped to take. “I cannot vote solely to protect an institution,” Sen. Patrick J. Leahy (D-Vt.) said Monday, arguing that he could not “ratify” Mr. McConnell’s past behavior.

Anger about the majority leader’s cynical power play may be clouding Democrats’ judgment, even about their own tactical interests. They have tried to paint Mr. Gorsuch as unacceptably radical, despite the fact that former Obama administration officials, the American Bar Association and many others have deemed him well-qualified to serve. Moreover, postponing the discussion over abolishing the filibuster until Mr. Trump’s next nomination, if any, would put Democrats in a stronger position and at least might pressure the president to select a more reasonable nominee next time than he otherwise might.

(Jenny Starrs/The Washington Post)

Yet more than partisan interests are at risk in the current fight. As Mr. McConnell has often noted, eliminating minority rights in the Senate means that when the political tables are turned, Republicans will be the ones with minimal influence on the future of the court. Just as Democrats should recoil at filibustering Mr. Gorsuch, undercutting decades of tradition, Republicans should recoil from the thought of permanently curbing minority prerogatives.

The Senate is on course to give everyone something to rue.