Politics is about leverage. Right now the Biden campaign and the centrists are using the threat of Trump to extort the left into falling in line and accepting the minimalist program. Turnabout is fair play. The progressives are collectively doing the same thing to extract concessions from the Biden campaign.
A lot of people who are ostensibly “Bernie or Bust” aren’t actually committed to not voting for anyone but Bernie. They’re posturing to get Biden to concede to add Medicare for All to his platform.
You can make the case all you want that people should “Vote Blue No Matter Who” because Trump is an “existential threat to the republic” and you may be right. And that may convince a lot of people, but it probably won’t be enough to win the election. Maybe it will? Who knows.
What will unite the party is concessions to the progressive wing. Biden will be less willing to make those concessions if he thinks the whole party is in the bag out of fear of Trump. He’ll have more incentive to pander to the right — something he has done throughout his career — in an effort to court the apocryphal “moderate Republicans,” whom he thinks are his ticket to winning.
Further, most of the people who are genuinely “Bernie or Bust,” like me, live in safe states, and there’s really no practical reason for us to vote for Joe Biden. I will never vote for him because I don’t want him to have a proper mandate. I will not legitimize this broken system or reward a party that has failed the American people over and over and over again.
Lastly, you should not direct ire toward the individual voters but rather to the party which manufactured consent for a candidate who by every metric (money, organization, enthusiasm, volunteers, youth vote) spells loser.
They are the ones ransoming are future. They are the ones who care less about defeating Trump than they do about preserving their own power. Put the screws to them instead of joining in the chorus of people trying to browbeat the left into submission. Their lack of an affirmative vision of the future is what gave us Trump in the first place. Insist that they actually be for something rather than merely against Trump. The constant lowering of expectations made Trump possible, and you don’t think things could get worse, just wait.