Thank you.
For those of us who are actually studying Economics (I'm getting my masters right now with the goal of a phd soon), we have respect for math and metrics, because they are necessary tools in order to make arguments (whatever that argument may be). The people who just say "no just free markets, lower taxes, etc" use almost no math models. I'm sorry, but if you're going to talk economics, you HAVE to talk to me with metrics, meaning regression models, calculus, linear and non-linear programming, matrices, etc. If you can't do that, then you don't even have a right to talk.
Paul Krugman is a legit economist, and though I don't always agree with him (and even sometimes spots mistakes he makes), his overall statement about us having a healthcare problem,
NOT a debt problem, is 100% correct.
Every mathematical model has shown that in the long run (a good ~30-35 years, it depends which model you run) our healthcare costs are unsustainable, but it's not because of medicare, but it because of the inflated costs in the private sector of the healthcare industry. Regardless of what you do to medicare (even if you eliminate it, which of course is NOT the right thing to do), the problems of health COSTS still remain. Therefore, it's not the actual concept of medicare that's the problem, it's the fact the health insurance companies can artificially drive up costs, and that big pharma can maintain monopolies thanks to patents that is the problem.
What's the solution???? Simple. We have to have a healthcare system that is just like every other industrialized country on the planet that has longer life expectancies than we do (Northern Europe, Western Europe, Japan, and Australia). In fact,
if we had a healthcare system like any other industrialized country with a longer life expectancy, we wouldn't have budget deficits, we'd have budget surpluses. The following is an excellent calculator that allows you to compare healthcare costs in relation to our budget and those countries (warning, math NECESSARY):
http://www.cepr.net/calculators/hc/hc-calculator.html
So in all, we DON'T have a debt problem. We have a healthcare problem.