Max Boot opines in today’s WSJ that ObamaCare is a threat to U.S. global military power, and, by extension, a threat to global security. I disagree. Because we should be seeking to offload some of the costs of policing the world, I hope that our current fiscal difficulties will force an ultimately worthwhile trade-off.

To be clear, I share Boot’s disdain for this massive expansion of federal power. Similarly, I don’t dispute Boot’s characterization of the health care legislation as likely to impose a huge net cost. Rather, the central flaw in the piece is his unwillingness to think clearly about our government’s obligations to our citizens, and of other governments to theirs.

The rationale whereby the U.S. government defends other countries, and U.S. taxpayers pay for it, is flawed. Under our Constitution, the American people grant to the federal government explicit powers to protect and defend the security of the United States. Treaties negotiated during the course of the Cold War effectively equated the defense of other countries with that of our own so that today the U.S. government provides “public goods” for people who are not now, and have never been, parties to our unique social contract.

As such, today’s U.S. military chiefly fights other people’s wars, and builds other people’s nations. The primary role of the U.S. Department of Defense is the defense of others.

These commitments have been sustained since the end of the Cold War under the premise that the costs are both low and sustainable over the long term. But it is becoming harder and harder to maintain these pretenses. By seeking to provide global public goods for all of humanity, we are saddling our children and grandchildren with huge costs.

Fiscal pressures have the potential to cause the American people to scrutinize military spending, and this scrutiny could ultimately force Washington to revise some of the core assumptions that have driven force planning for a generation. If that happens, we might finally shift the burdens of defense spending back onto those who benefit from such spending.