My comment wasn't really fleshed out, but my point is that it has to be something besides actual inequality because people can't perceive inequality directly. They can perceive their purchasing power and labor-selling power going down (could be all of society rather than equality). They can perceive inequality through trusted news media (NSA/security definition of can break you. I certainly do not mean trustworthy).

I am not trying to deny inequality as a driving factor. I do agree that inequality has been going up, I do agree that inequality is a society-destroying problem, and I do agree that this has created a fertile ground for the destructionist movement. I just think there needs to be a little more to the theory for it to make sense.