There are 327,000,000 Americans. Only an idiot would imagine that they all think the same way on any subject, that they all have the same levels of knowledge and education.
No American I know personally thinks the world is flat or that wind turbines cause cancer. However, I travel abroad a fair amount for professional reasons, and I've heard some really loony things from people in foreign countries.
In other words, there are morons all over the planet. No one has a monopoly on stupidity.
Generalizations about any group are symptoms of ignorance, dear.