You have it closest, IMO, in stating that they're confused. While I agree that liberals tend to support all those things listed in the essay, I think most of them don't have any guiding principles at all, how else could they endlessly support contradictory positions?
I think "liberal" is a person who automatically opposes anything a conservative proposes or stands for. Since they flip flop so often, like JFK, I can find no other reason for their negative disposition.
Well, if FreeRepublic is any indication, the above definition will do just fine for conservatives, too. I'm series, actually.