Liberals believe in Keynsian economics not Marxist policies so its not like anything in their philosophy would destroy America. The main difference is Liberal uses Constitutional ideals only when they are not in conflict with the advancement of social justice. Conservatives tend to adhere to the constitution even when it stands in the way of social justice.
If Liberals were in power American government would be like Sweeden's government, in which we would have very high taxes and less, but still substantial private land ownership.
Bush is actually a Liberal under the traditional definition because he has strayed fairly far from the Constitution, limited states rights, and expanded the economic and authoritarian powers of the federal government.
Liberalsim doesn't always accompany an increase in government authority though in administering full social control, if it did, we'd end up like the USSR, while Conservative authoritarianism tends to approach fascism when everyone works hard and competes but ultimately serves government ends.
Libertarianism is the unspoken third route, in which you make the government the people's bitch so it can't create damaging economic and moral situations.
People are difficult to govern because they have too much knowledge.
When there are more laws, there are more criminals.
- Lao Tzu
