During the 2016 presidential election, it made sense for Donald Trump to go after Hillary Clinton. The former secretary of state was, after all, his rival at the time, and over the course of the campaign, the two traded plenty of rhetorical shots.

But after Election Day 2016 had come and gone, common sense suggested that the Republican would shift his attention. He’d won the race. Clinton had exited the stage, transitioned to retirement, and expressed no interest in pursuing office again. Trump had every reason to focus on governing, and no reason to target his former rival.

He did it anyway — repeatedly. In fact, when Trump launched his 2020 re-election campaign, he devoted much of his speech to Clinton, despite the fact that she wasn’t running. With just weeks remaining before Election Day 2020, Trump not only pushed then-Secretary of State Mike Pompeo to uncover and release Clinton emails, he also lobbied then-Attorney General Bill Barr to prosecute Clinton for reasons unknown. (This was before the GOP pretended to care about the “weaponization” of federal law enforcement.)

None of this made any sense — she was neither on the ballot nor on the campaign trail — but Trump couldn’t help himself. He’d invested so much time and effort into hating Clinton, he apparently found it impossible to end his offensive.

And now it’s happening again.

After President Joe Biden announced that he was withdrawing from the 2024 race, it stood to reason that Trump would curtail his attacks for a painfully obvious reason: The Democrat would no longer be his opponent. There was little to be gained from additional rhetorical barrages.

But just as the Republican couldn’t shake his hatred for Clinton, as The New York Times reported, he’s still ranting about Biden, too.

In his posts since Mr. Biden’s announcement, Mr. Trump has so far not taken direct aim at Ms. Harris or other popular Democrats who have at various points been mentioned as possible options for the ticket. Instead, Mr. Trump has fallen back on attacks on Mr. Biden that largely echoed the ones he has been making for years.

The GOP nominee responded to Biden’s news on Sunday with ugly tirades and conspiracy theories. It was in Trump’s interest to take the high road, but he apparently didn’t care.

A day later, the former president kept going. “It’s a new day and Joe Biden doesn’t remember quitting the race yesterday!” he wrote to his social media platform on Monday morning.

This morning, Trump offered more of the same.

I won’t pretend to know what’s on the Republican’s mind, but if Democrats are lucky, he’ll keep up the anti-Biden hysterics indefinitely.