Well, I didn't mean to say that only a broad historical context is valid for understanding the different. I'm just saying that every single political movement in American is pretty much from a "Liberal" background so we should take those labels with a grain of salt.

I also think there is a tendency to confuse how the terms are used. They often are used to refer to people's moral or ethical positions--i.e. being an advocate of gay marriage is often called "liberal" and opposing them often called "conservative". But people divided on that kinf of social/personal issue might be in complete agreement about budget priorities or military spending.

In the social/moral sense, "liberal" is often meant to denote a position of that challenges "old fashioned" or "traditional" notions. I don't think that has much in common with what could be called "liberal" in the political spectrum.

I think this is where the idea of "liberal media" comes from. Because the media is often controversial in it's portrayal of unconventional lifestyles and issues surrounding them, it's confused in being supportive of a political agenda that is also called "liberal".