I think you are probably unaware of how ridiculous the evangelical movement in the US actually is. It's not based on reason. I think it's the closest analog to Muslim fundamentalism that you'll find in the Western world. These people actually believe the Bible mentions the US, that the US is a nation chosen by God. There's a lot more to it and I don't want to write a 10 page post on evangelicals, so I'll give you a link that might supply some context. It's a 6-hour program, but if you really want to understand, this will give you some important background.
P.S. I grew up in an evangelical family, in a county that was dominated by evangelicals. My perspective is not actually based on this PBS documentary, the documentary just coincides with and explains what I have experienced.
Look at this thread if you want to see why evangelicals might be uneducated. There is one poster who actually believes higher education institutions are brainwashing people. That position is one that many evangelicals subscribe to. It's not an outlier. Many of them truly believe that in order to reject the Bible (and accepting scientific theories like evolution is the same as rejecting the Bible to them), you must have been brainwashed.I may not going to say if they are right or wrong; but I don't really understand how any of those points would show a lack of education.