Its a very difficult question, and probably the most important question we face over the next 30 years. I think the answer is a combination of your #3 and so-called "death panels". Means testing is a fine idea but its not going to save much money unless you really hit the middle class.
Homer: [looking at watch] Two hours? Why'd they build this ghost town so far away?
Lisa: Because they discovered gold over there!
Homer: It's because they're stupid, that's why. That's why everybody does everything.