I'm not sure if the guy in the preview image is really engaging in cognitive dissonance, or is just an unrepentant asshole and borderline sociopath.
How many of these people are really trying to reconcile their self-contradicting claims, and how many just mouth excuses they don't really believe, because it's their justification for selfish actions?
Keep in mind a lot of people think being an asshole makes them "badass" or "strong" or whatever. It's why they fell for Trump, he is an ass. The mean-spiritedness and cruelty isn't the problem, it's the point.
If Americans aren't given the option to vote to improve their atrocious material conditions, they will find a way to vote for somebody that will cause harm to the people they perceive to be their enemies.
Michael Moore described Trump as a human molotov cocktail, and that's the best description of how his supporters see him imho. They don't get anything from him but at least he hurts the people that screwed them.