That’s what happens when people in a geographically huge country lack education or direct interaction with the outside world. They buy into right wing media bullshit. The script is carefully crafted to appeal to people who have never left their own backyard, and who lack the critical thinking skills to deconstruct the narrative. The US has a much larger backwoods area than any other industrial country. So you end up with millions of people who don’t really know anything about the world and, thus, are ripe for the picking. Ignorance is the root of fear. Fear breeds anger, and the mainstream right wing media is very good at playing to that ignorance, and reinforcing it with the chorus of “RAH RAH RAH! AMERICA FIRST! RAH RAH! DIRTY LIBERALS! ILLEGAL IMMIGRANTS!” The reason you get a cultural divide is that the US does trade with the rest of the world and, naturally, that happens along the coasts. So, you get people who interact with the world, have the money to invest in education, and as a result have more enlightened, liberal attitudes and values. The further you get away from the trade hubs, you more you find the cocoon mentality. That, and the United States is a really young country with little history to draw from. So if people here aren’t learning from the older industrial countries that have already made all the mistakes (like privatizing municipal services) and learned what not to do, they make those same mistakes themselves.