We can't afford it. Some people like Michael Moore say that we should just divert funding for the war toward Socialized Medicine, but the fact of the matter is is that we can't afford the war either. We are already borrowing money to finance a lot of the dumb programs already in place. Government spending is out of control, and we need to exercise budget restraint now, not consider new areas to increase spending.
Your subsequent examples are filled with financial fail. Chemo? No, you just died. However, you died without invoking tens of thousands of dollars in average treatment costs. Cancer survival rates are still terrible. Obviously, a lot of people are spending a lot of money and just end up dead (or dead soon enough) anyway. How exactly is THAT a better system of healthcare?
If you get cancer and it's late stage, just go home and die with dignity. Don't run up (by then) a good $100K in bills just so you can have 2 years of terrible treatments just so you can linger for 2 more years and then die of the same causes anyway.
Look, what I'm saying is that we CAN and MUST get by without socialized medicine in the USA.
CAN = We used to keep ourselves healthy with eating right and exercising. That's most of the healthcare battle, right there. Past that point, you can buy "catastrophic health" insurance.
MUST = The Hypercapitalists are in solid control of the nation and there's going to be no sharing of that power with the general public without resolution by civil war. Barring the war, it's not going to get better. The prudent man would conclude that common healthcare is going to continue being priced out of his ability to pay. The prudent man would then plan accordingly; that means paying a lot more attention to your personal, preventative actions.