Why do people ignore the bad things Trump has done?

Because people are tribal and are bound by their confirmation bias. Think about when the news reports something negative about any politician. The politician’s followers are first immediately skeptical, then if/when it is found that the allegations are correct, the people who love this politician make excuses, minimize the action, or bring up something negative that the other side has done.

This type of behavior is certainly not unique to conservatives or Trump followers. You see this type of tribalism in politics, religion, and even sports. There is an irrational hatred for the “other side” and irrational love for those on “our side” merely because they are on “our side”.
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