Well, in all honesty, John might be able to answer this more than I, but I think what we think of as "liberalism" today (in economics) came about as a result of the Great Depression. I only know what I've heard from my dad and mom, but a lot of people were hurting back then and the government came in and gave people "make work" jobs and assisted with getting people back on their feet.
The REAL problem is, though, that even if we all agreed that these programs like medicare, social security, medicade need to end how do you get there from where we are now? I remember when I was in college 30+ years ago they were talking about how the baby boomers would affect social security, etc., but no one was willing to address it and chose to push it on to another generation. Now, with the boomers about ready to hit retirement age, social security and medicare are going to be pushed to the limit.
MY belief is that it's up to the conservatives to take a stand. That's what they preach. The liberals won't be cause they believe in it. The conservatives alone could actually address it, but they won't because they think it's political suicide. I personally think that the American people are looking for courage and leadership. Something sorely lacking today and in all candidates upcoming.