If you have ever wondered how people can support Donald Trump, when he lies constantly, then you have to watch this video from John Oliver:
The problem is a combination of a propaganda-like appeal to emotions, reinforced by a fake news industry. Note that this kind of non-rational belief is not confined to conservatives. For example, non-rational belief in things like “chemtrails” and the idea that immunizations cause autism are also common among some progressives. And just because you are intelligent, you are not immune. Steve Jobs was extremely intelligent, but he famously delayed getting treatment for his cancer because he didn’t believe in traditional medicine.