In the large, yes, it needs to be an economic question, simply because there isn't enough health care to go around, and there likely never will be. So you are

In the large, yes, it needs to be an economic question, simply because there isn't enough health care to go around, and there likely never will be. So you are left with a question of allocation and rationing (no matter if it's government or private market rationing). So you need to figure the most cost effective ways of administering health across the population. Ethics falls into this as well, but is weighed against cost. (see Britain's drug board approving end-of-life drugs that add only a few weeks to life at large expense -- NY Times had something about it) Basically, the flaw in your argument is that there's a presumption that there is infinite supply, and it just costs money to get at, so more money thrown at the problem (ie. more tests, prevention) means more treatment. But it doesn't work that way, it's a tradeoff. The doctor testing you for cancer today is not treating somebody who actually has it today. (simplistic, yes, but you get the point).