That's the question no one in the government is asking. we are capable of providing a lot more care than most people can afford. But that's fundamentally no different than anything else - we can build nicer houses and fancier cars than most people can afford. So how do we decide who gets the mansions and the ferraris? The debate right now is like arguing over the paint job, we're still pretending everyone can get a sports car. Obamacare is a step towards rationing but I don't think it goes far enough to actually be effective - I fear we're replacing one broken system with a different broken one. That is assuming it won't be overturned by the courts - today yet another state ruled the individual mandate unconstitutional.
Personally I don't believe a single payer system is best - there's nothing wrong with high costs as lost as they result in high value. To me innovation is more important than cost savings and I'd rather have the most advanced system rather than the most cost effective system. Now if only more doctors/hospitals/insurers could start using technology effectively. Like this guy: