They are fighting to usher in a brand “New America” that has no resemblance to the old America that they hated so much. I’ve honestly had leftists tell me that they are true patriots because they want to correct all the wrongs in the country and transform it into a better place. It just looks like they are trying to destroy the nation to me and replace it whole cloth, but that’s not the way they see it.
When you point out that there's nothing keeping them here, and that they could always move to the utopia's they believe exist elsewhere, they look at you dumbfounded and say "but we don't want to leave".
Cognitive dissonance is too polite of a term for people like that.
This is the "diverse" America they advocate:
Real "diverse", huh?