After Carter lost to Reagan (with much thanks to the Religious Right, the early Christian Nationalist movement organized into a voting bloc by Jerry Falwell), both parties have been terrified a primary challenger to an incumbent president correllates to a loss of the White House, so Biden staying in is the default, and is a known quantity, since he has four years of being president on his rèsumè.

Anyone you replace him with loses the incumbent advantage, which is a significant number of people who vote for the incumbent regardless of party.

It's greater hubris to assume we can safely replace him without losing votes than it is to keepmhim even if he was doing his Post-October 2nd 1919 Wilson impression.

According to Bob Woodward ( Fear: Trump in the White House the finalé of the book) Ty Cobb quit as Trump's lawyer regarding the (still open) investigation into Russian interference in the 2016 United States elections, because he realized that if Trump were not president, there would be a sound case that Trump had diminished capacity to be resposible. But Cobb couldn't make this claim since that would mean admitting the President of the United States was mentally incapable.

Now I am down with the notion that we should have a system in which unconscious presidents and mentally unfit presidents are revealed and the chain of command is rapidly implemented. But that would assume the US is not run by an aristocratic elite, which it totally is. And hence no cabinet is going to admit that Trump neither can comprehend the job nor can be adequately controlled as a useful idiot.

So even if we assume Biden is daft like a domestic turkey, he's a better choice than Trump.

And that's before we confront the reality of the Heritage Foundation's Project 2025 which Trump is happy to facilitate, is intended to dismantle all remaining democratic feature (lower case) of the United States. It includes an Ermächtigungsgesetz (as much as an authoritarian president needs one after Trump v. United States (2024) ). A vote against Trump is a vote against Project 2025 and one-party autocracy, whether it's Biden or whoever (or a sack of potatoes).

Yes, it may be King Log or King Heron yet again, but Biden has gotten more done than we typically can expect from neoliberal logs. And he (or his handlers) might recognize the mandate that obligates him that the US isn't staring down the same threat in 2028.

Or, as the Republican party is looking not just to expand its usual election shenanigans of gerrymandering and voter suppression to include intimidation, violence and defrauding the Electoral College process, but is also looking to spearhead a barrage of procedural and violent coups d'etat, and may even incite civil war. So all our efforts to stop the Heritage Foundation's offensive may be moot, no matter who is on the ballot.

I'm still voting blue regardless, because the outcome is not yet determined, only that Republican knives are out.