That's it in a nutshell, adianoeta intended. Enter a conversation with one of these creatures, tell him or her or it that you're a conservative, and you tend to be treated with a solid stream of "you believe" accusations that is a safe but rather sterile substitute for political discourse. I once heard a conservative friend accused of attempting to establish a theocracy, which was amusing in view of the fact that he was, at the time, an atheist.
Mostly it's fear. These ostensibly "free" thinkers are so locked into their narratives and their stereotypes that real political discourse turns out to be awkward because it threatens tribal boundaries. There are, to be sure, conservatives plagued with this same limitation but it's endemic on the Left.
"Us" and "Them" describes their entire social and political argument.