My current working metaphor of political philosophy changes from time to time as I gain insights, or the previous metaphor fails to explain the behavior. It goes something like this:
Conservatives (in the normal usage right to extreme right of center - typically republicans or tea-party) are children looking for a Father Figure. They're willing to give up other peoples liberty for the illusion of safety, although they get annoyed when their own liberties get trampled. They want someone to tell them, at least once a week, how to behave and what to believe. They're positive that they're right and are willing to use the force of law to make you behave the way they want. They'll happily tell you what the bible says you should do, then go do something that you shouldn't.
Liberals (in the current usage - left of center progressives from democrats to socialists) are children looking for a Mother. They want some one to kiss it and make it better. They get mad when they don't get the toys they know they deserve and are always asking for more. They're terrified of how they'd behave if they had the chance, so they're positive you'd behave just as badly. They also are willing to use the force of law to make you behave the way they want. They're all about sharing - as long as it's you sharing with them. What's yours is mine, what's mine is mine.
Greens (radical environmentalists) are like the crazy miser uncle who won't be happy until we're all freezing in the dark. They want alternative energy as long as it's not any of the alternatives we have available. Human beings are not part of nature and the world would be much better off if we'd all just go away.
Communists are the aunt that came to visit twenty years ago and has been living with you ever sense, except she's on LSD. They can look at the elite that rule them and think - I'm just like them. They've convinced themselves that a lower standard of living is better - (mostly because it doesn't give you time to think about just how screwed you are). They believe if everyone is treated like a half broken tool, then we've achieved social justice.
Libertarians are the adults and are looking to get on with life.