Is it the institutions that cause divisions, or is it the divisions that cause the institutions? I don't think this answer is as clear as you suggest, because a great deal of beliefs and ideologies are passed down by institutions such as schools, which are of course mostly government controlled. Is it merely a historical artifact that the US has so many creationists?
I use Canada as an example because I think it's interesting how two countries that were basically founded by the same people (European settlers, mostly British in the early years) have diverged so greatly in both governance and ideology.
The fact that two groups are both European settlers does not mean they're basically the same people. Would you say that the Barbadian slaveowners who founded Charleston, South Carolina, and heavily influenced the culture of the South, are basically the same people as the Quakers and Puritans who founded colonies further north? They did not see themselves as the same people, and ended up fighting a bloody war over it, which they've been refighting politically ever since.
Is it merely a historical artifact that the US has so many creationists?
Perhaps. I think it's basically a product of separation of church and state. If everybody is free to practice whatever religion they choose, a fair number will choose religions that have nutty beliefs.
I don't think institutions like schools have fostered these kinds of divisions; if anything they have reduced them, by putting everyone through the same indoctrination. As much as the US seems politically divided now, it was more so in the 19th century, before compulsory public education.
i think it's geography. people don't realize how significant geography (and geology) is in the determination of culture. in the case of the U.S., "cultural diffusion" is restricted by the geographic distance between towns/cities
it is only now in the internet age that these cultural distances have begun to erode
I use Canada as an example because I think it's interesting how two countries that were basically founded by the same people (European settlers, mostly British in the early years) have diverged so greatly in both governance and ideology.