Most "liberals" don't come to their conclusions on their own. Every morning, the New York Times or Washington Post tells them what to think and what to say. As a liberal, all one has to do is repeat the words (and send them in as letters to the editor of your local paper) -- and even plagiarize them as though they are one's own. It doesn't matter that it doesn't make any sense -- as long as they keep repeating them, because repetition will give them a ring of familiarity, if not truth. Tomorrow, the next demagogue will give them their marching orders. All they have to do is obey the new mantra of the day -- and stick together because they are nothing if they try to stand alone, as individuals.
They never need to have original ideas; all they have to do is be against what some thoughtful person is for. That makes them just as important.
I see it that way too. The media never stops hammering in the leftist point of view, and the sheep take it as gospel, never realizing there is an agenda, and not believing it if you tell them. I guess it's called conditioning. No surprise that elements of socialism are now seen as American tradition.