Yeah, Americans aren't particularly gullible. But we are ignorant. There is a lot that the average American doesn't know about the world. It's not really our fault though. It's just that the American government's (mis)education system is particularly good at keeping people from knowing certain inconvenient facts, especially in the realms of history and government policy such as the wave of racism that started the War On (Mexicans' and blacks') Drugs back in the 30s.