Many years ago talk show host
Chris Matthews came up with an interesting formulation:
He said the Democrats were the "mommy party" and the Republicans the "daddy party." That is, the Democrats were "nurturers," concerned with health policy and day care. The Republicans were "protectors," taking care of national security and other manly matters.
I think the same is basiscally true of liberals v conservatives.
A liberal is someone who trusts the government with meeting social needs. A conservative is someone who trusts it with meeting security and military needs.