For a liberal? These are the same people who question reality itself. Start there, and you'll begin to understand, at least as far as is possible to "understand" the lunatic left. Some are complete skeptics against reality (skeptic tanks).
I once was talking with a guy about why we are going to war with Iraq. Of course, being a clueless liberal, he stated oil (ignoring the fact that his car needed oil and gas to drive him to work that day) and American imperialism (ignoring the fact that Iraq attacked Kuwait and is violating their terms of surrender) as our entire motive. Somehow he switched over onto the subject of reality and told me that "we can't even know" if the desk that was sitting next to us is real or not. I knew then that no matter how reasoned my arguements were, I was not going to get through to planet mars on this occassion.