KIMBERLY STRASSEL: The Payback for Mar-a-Lago Will Be Brutal.

Democrats may be betting that adverse coverage of Mr. Trump will help them in November, or in 2024. They’d better hope so. Their media defenders recklessly ignore the boomerang history of unleashed governmental powers and the long-term political danger of violating precedents and norms. A Democratic Congress enacted, and Jimmy Carter signed, the first independent counsel law in 1978. Two decades later it led to Bill Clinton’s impeachment.

If anything, a perceived political persecution of Mr. Trump could help him to a second term. And he would be even more unrestrained as the 47th president than he was as the 45th. A second Trump administration wouldn’t have the caliber of grown-ups who signed up for the first tour. Mr. Garland’s raid has made even the highest political figures fair prosecutorial game, and the media’s new standard is that the department can’t be questioned as it goes about ensuring “no one is above the law.” Let’s see how that holds when a future Republican Justice Department starts raiding the homes of Joe Biden, Hillary Clinton, Barack Obama, Eric Holder, James Comey and John Brennan.

Payback could come even sooner. Democrats set a new low with their Ukrainian impeachment circus, and a GOP House next year might be up for a reprise. Get ready for a few more select committees—perhaps excluding the minority party, as the Democrats effectively did with the Jan. 6 committee—to investigate Mr. Garland’s politicized department or Hunter Biden’s finances. Watch them subpoena sitting Democratic representatives, as the Jan. 6 committee did to Republicans. Reps. Adam Schiff, Ilhan Omar and Eric Swalwell may find themselves on the back bench with a new Republican majority eager to follow Mrs. Pelosi’s example and strip the opposing team’s members of committee assignments.

All this tit for tat will further undermine our institutions and polarize the nation—but such is the nature of retributive politics. Which is why the wholesale Democratic and media defense of this week’s events is so reckless. Both parties long understood that political restraint was less about civility than self-preservation. What goes around always comes around. What went around this week will come around hard.

To coin a 2016-era Insta-phrase, choose the form of your destructor.