WHY ARE THESE PEOPLE SO STUPID?

A couple of days ago, a female caller to Hannity's radio show said she went to a liberal college and came out a Marxist. Today, Dr. Helen replies to a letter from middle/high scholl teacher who's worried that his students are becoming "whole new generation running on Marxist ideology." The teacher's one example of "Marxist thought" was a 4th grade girl who claimed that Bush caused 9-11. As far as I know, this claim isn't tied to any political ideology.