Whether you're surrounded by them depends a lot on your rank. My brother is Navy here in Australia. He's not a clever guy, and he's on the right.

However, I've met some of the people he worked with in leadership positions, and they're at worst centrist (or at least know how to keep quiet for the sake of being amicable)

That's not to say being smarter innoculates you against a culture of indoctrination, but it does seem to be strongest at the low end of the spectrum.