The U.S. defense budget is a form of national security welfare.
Rich Lowry follows Max Boot in warning that spending a little less on defense in favor of expanded entitlements will lead America to the blighted Hellscape that is modern Europe. Specifically, they fear that increased domestic spending will come out of the Pentagon's hide, diminishing America's global power and forcing us to behave like cowardly, cynical Europeans. That's the pitch at least, but the reality of the conservative position is a bit more nuanced. The argument, in a nutshell, is that other countries have a higher claim on American taxpayers' income than U.S. citizens do.
Of course, this isn't stated so baldly but it is the reality of the Lowry/Boot argument.
It's widely understood and indeed celebrated by conservatives that America's defense posture is a "global good" - i.e. something that the American taxpayer provides for the sake of the world (and, the theory goes, ourselves). American taxpayers sustain a military establishment vastly in excess of what is needed to defend the continental United States so that we can also defend South Korea, Japan, Europe, the Middle East, Israel, sea lanes, freedom, etc.
We cultivated these countries and regions because keeping them "open" to the U.S. economically and politically was a vital strategic interest at a time (the Cold War) when a rival power sought to close them off. And we kept Asia and Europe (and now the Middle East) open to the United States by making them dependent on the United States for that most basic of need, their security.
In the context of the Cold War superpower standoff, such a strategy made sense. They were insecure and weak, the Soviet Union was aggressive and Communism had taken root in Asia. But when the Cold War ended, we not only refused to ween our dependents, we added new ones to further the new and unsustainable ambition of global hegemony. The end result is that the American taxpayer provides the global security equivalent of welfare to countries that are, with few exceptions, wealthy, industrialized and fundamentally friendly to the United States and the current international system.
Before the health care bill was even a gleam in Obama's eye, the U.S. was shoveling over billions upon billions of dollars in welfare payments internationally even as the strategic rationale for doing so had completely dissolved.
I am very sympathetic to anyone objecting to new federal entitlements on the grounds that the country is already reeling under debt. But to say we shouldn't spend our own money on ourselves so that other countries won't have to bump up the amount of GDP they devote to their own defense budgets strikes me as perverse.