Well some ideas aren't based in reality. Brexit was anti-immigrant policy, and used non immigrant based lies to bring regular people onboard the idea. Aka the lie that 350 Million Pounds would go to NHS instead of EU. https://www.independent.co.uk/news/uk/politics/final-say-bre...
That coupled with the idea that every country thinks it's special, no one in America thought that kind of broad faced lie would happen in USA. Welcome to the new reality. I worry that the only way we have smart world leaders again is if they make a huge lie that gets ignored by some world event. Example: George W Bush and 9/11. No one worried about his promises afterwards, because national security was the prime focus.