The US goobermint spends more per capita on healthcare than the UK's one.
The UK system covers everybody.
The US system covers veterans, the very old and some of the very poor.
While it's true that some countries don't pull their weight defence wise, it would appear that it's something else that's stopping you having something like the NHS.
Take a look at our political system, and who it puts in charge.
I have a hard time finding a nationally elected US politician that I would be willing to put in charge of the contents of my trash can, let alone anything actually relevant or important.
Especially when looking at the presidential election this year, would you trust *either* of them to actually spend the money on proper health-care instead of using the money to buy votes or line their own pockets?