The Democrats are doing it again. If Ruth Bader Ginsburg had resigned from the Supreme Court during Barack Obama’s first term as president – when the Democrats controlled the US Senate – then Roe v. Wade would still be law. Obama would have replaced Ginsberg with another liberal justice and there would still be, today, five votes at the court preserving Roe. Instead, Donald Trump replaced Ginsberg with Amy Coney Barrett several years later and the court overturned Roe by a 5-4 vote.

Joe Biden is committing the same mistake Ginsberg did: he’s staying on the job too long. The implications, however, are far more ominous. What’s been obvious for some time now was painfully clear during his debate Thursday with Donald Trump: Biden needs to step aside. And by refusing to, he may cost the Democrats the presidency and all the vital powers that come with it.

Biden is a good man, to be sure. He has served his country admirably over many decades, in the Senate, as Vice President, and as President. And he ousted Donald Trump from the presidency several years ago, eliminating the significant danger a Trump victory would have entailed.

But he’s now bumbling and stumbling toward an entirely different legacy: as the man who gave the presidency back to Trump for no good reason.

Indeed, there are several big problems with Biden continuing to run for reelection. For starters, presidential candidates should be at the peak of their intellectual powers for the entire term they seek. This prerequisite shouldn’t be controversial. And yet Biden doesn’t qualify. Put simply, it’s irresponsible – for both Biden and his advisors – to continue trying to run the country at this point.

Second, campaigns are hard and there are still over four months to go. Being on the ground in key battleground states is vital. For all his flaws, Trump is more vigorous than Biden, by a wide margin. As bad as the debate was for Biden, it could very well go downhill from here.

Finally, independent voters will be key in November. Hardcore partisans might not be swayed by Biden’s debate performance. But independents surely will be. They will care, as they should, about the candidates’ vigor and ability to perform in one of the world’s most demanding jobs.

There’s nothing wrong with Biden being in his eighties. But there is something very wrong with clinging to positions of power for too long. He shouldn’t be president anymore – today – let alone seeking the job for four more years.

Ginsberg didn’t resign and conservatives eliminated the constitutional right to an abortion. Joe Biden should be applauded for his service to his country. And he should not seek another term as president.

William Cooper is the author of ‘How America Works… And Why It Doesn’t’.