The US military and priorities

This is little more than a simple question to get the new year rolling: Many people argue that the government cannot do anything without screwing it up. But we are clearly able to organize a large military force that can accomplish many diverse objectives, from invasion to foreign aid. And if the government can do that, I do not understand why it cannot find a way to provide basic health care for all of its citizenry. Is this a matter of ideology? Politics?

Maybe it's just a matter of priorities.