“The Biden campaign will surely calculate that the damage of dropping out will be far less than the damage of participating in debates.“
Biden’s problem isn’t risking fallout from chickening out - that would hurt him - but he’s got a far worse problem:
Biden is the challenger - he’s the one that needs the debates, not President Trump.
Think of it as a world heavyweight boxing title. As incumbent President, Donald Trump holds the title. He’s the reigning champ. If Biden wants the title, he needs to challenge the champ. He has to fight him in the ring.
A huge part of that challenge takes the form of debates. If Biden won’t get on stage and debate, that will be seen as withdrawing his challenge.
That is how people will view it. It won’t be so much that Biden was a coward - it will simply be that there is no challenge, so President Trump is still President.
A heavyweight challenger could have the best excuse in the world for not fighting - for example, let’s say he was abducted by aliens the day of the fight and there was video to prove it. So nobody could blame him or call him a coward.
But still, the champ would keep his title.
I think it’s the same for Biden. He has to debate or Trump remains President.
One thing they might try is have Kamala Harris challenge President Trump to a debate in Biden’s place. If President Trump refused, that could be spun as him chickening out. If he agreed, he’d lose the advantage of debating a senile old man.
If they try that, President Trump should say “Sure, I’ll be happy to debate her, or anyone the Democrats officially place at the head of the ticket.”
That would be checkmate Trump - because it is too late to get her on the ballot as Presidential candidate.
The candidate's name on the ballot is a proxy for Electors to the Electoral College. Voters are really voting for the Electors, so replacing the candidate will be allowed.
However, Democrats will have the burden of explaining the ballot to voters because they won't have grounds to demand existing ballots be changed or voided for new ballots.
-PJ