This is why I'm so dismissive of self-styled political moderates who argue that the path to political comity is to talk things out with political opponents, meet them half way etc. You cannot have political comity with people who don't value truth and don't adhere to rational methods of argument. Such people will lie about their premises, repudiate arguments they previously agreed to (either on their own initiative or because their political weathervane of choice has changed direction), and their promises are meaningless because they don't see any shame in breaking a promise with people they don't respect. Basically about 1/3 of the US has taken ont eh trait of narcissistic personality disorder at a group level.
I urge everyone to read Harry Frankfurt's short essay On Bullshit: https://www2.csudh.edu/ccauthen/576f12/frankfurt__harry_-_on...