4) Liberalism is a fundamentally immoral political philosophy. Ironically, given all their talk about "shades of gray," liberals have a very Manichean view of the world. They consider their fellow travelers to be on the side of the angels, while the people who disagree with them are treated as evil. This leads to an "anything goes" mentality when dealing with their foes: ignoring the law via a "living constitution," politically based prosecutions, shouting down opposing speakers, and treating lying about their agenda or opponents to be moral. On the other hand, liberals will support other libs, no matter how corrupt, sleazy, or vile they are as long as they're politically useful to the left. See Ted Kennedy, Barney Frank, John Murtha, and Robert Byrd for examples of that. In other words, as Margaret Thatcher has said of the Left, "For them, the end always seems to justify the means."
5) Liberals believe merely being liberal makes them good people. Liberals who're obsessed with money think they're compassionate because they give away other people's tax dollars. They believe they care more about the earth than other people, even as they fly around in private jets, because they babble on about global warming. They can be dumb as a rock, but believe they're smarter than most other people because they're liberals. In other words, in the minds of most liberals, liberalism is an all-purpose substitute for actual virtue instead of just another political philosophy.
6) Liberals have too much faith in government. Even most liberals would admit that government regularly fails the people. If you don't believe that, just ask them about the Bush Administration and they'll give you an earful. However, liberals tend to believe that with the right person in charge, government won't be so slow, stupid, inefficient, and badly run. Human history proves that they're wrong about that.
7) Liberals have minimal interest in whether the programs they support work or not. To most liberals, whether a government program betters people's lives is completely irrelevant to whether they'll support it. A program that doesn't work and costs billions, but sounds compassionate and helps Democrats politically is a huge success in the eyes of the Left. Once you understand that liberals think this way, their baffling support for programs that make no "common sense" is much easier to understand.