Europe wouldn't spend the agreed 2% of GDP on the military. Many presidents for many years tried to make them comply with the agreement, but they just ignored it. It was thought better to spend on the healthcare of the public and mock Americans for not having universal government healthcare. Many people in countries in Europe, like Spain and Ireland, that effectively don't have militaries, are still laughing and mocking.

Again, this was a considered policy choice on the part of the United States. Unipolar military supremacy bought us a quiet Europe, a stable and high dollar, and the ability to set the terms on nearly every other negotiation we made with European countries. This was an intentional trade: we will spend on the military so you don’t have to. In the wake of the fall of the Soviet Union, some US policymakers deluded themselves into thinking geopolitics didn’t exist anymore, and so we’ve come to start bitching more about our side of paying that bill, but we bought the American century with military spending.

And, to be clear, the US not having health care is a policy decision on the part of the US, not some lack of funding, as becomes clear when one looks at the expenditure per capita on healthcare in the US compared to other developed countries.