Ego
When I say ego, I specifically mean the cognitive biases that dissuade people from thinking ill of themselves and their past actions. I wouldn't say that people "dislike being wrong", though that is useful shorthand, but people are very good regardless at avoiding or recontextualizing information which would make them feel bad about their past actions. And when it comes to politics, people have a lot of past actions, a number that is constantly increasing.
I describe the strength of one's ego as the ability to take hits to self-esteem or to recognize that past actions were incorrect. By this definition, a person who cannot take criticism and always praises themself has an extremely weak ego - usually, but not always, caused by being abused as a child.