 What's at stake for the Democrats is not the next four years, it's the next 12. So what they're going to do with Biden will be directly related to who Trump picks as a VP. If they see his VP pick as a threat, they'll replace Biden with someone they think is strong enough to give a run against Trump. If they don't see him as a threat, they'll let Biden run out or they'll put Kamala in, who they know is going to lose. They'll count on 100% combative action.