Is NATO a military alliance or social club? The “North Atlantic” Treaty Organization just invited Montenegro to join. With 2,080 men under arms, Podgorica is a military nullity.

As I point out on National Interest online: “Adding Montenegro to NATO is like accumulating Facebook Friends. They do little more than allow preening Washington officials to wander the globe gloating how popular the U.S. is.”

During the Cold War NATO was viewed as deadly serious. For years war seemed to be a real possibility.

Then the Soviet Union collapsed. The quintessential anti-Soviet alliance no longer had anything to defend or defend against.

As Public Choice economists would predict, institutional instinct took over. Supporters subordinated the military to the political, and NATO became a geopolitical Welcome Wagon for former Warsaw Pact members.

The good times came to a halt last year with the Ukraine crisis. The Baltic States suddenly looked vulnerable and alliance members remembered Article 5, which committed them to battle against a nuclear-armed power to protect largely indefensible nations. Americans and Europeans were expected to risk nuclear war as an act of international charity.

Proposals to add Georgia and Ukraine would multiply the dangers. Russian aggressiveness, though unjustified, illustrates how important Moscow views its influence in both nations. Nothing in Kiev or Tbilisi is worth a nuclear confrontation.

The problem is not just NATO’s recent expansion. Turkey also is undermining U.S. and European security.

Ankara spent years prosecuting a brutal campaign against Kurdish separatists and occupied more than one-third of the Republic of Cyprus. Turkey has turned in an ever more authoritarian and Islamist direction as President Recep Tayyip Erdogan dropped his liberalizing pretensions.

Worse is Ankara’s irresponsible shoot-down of the Russian plane. Turkey may have been protecting the illicit oil trade or insurgents in an area dominated by the al-Qaeda-linked al-Nusra Front, or attempting to punish Moscow for backing Syria’s President Bashar al-Assad.

The first two undermine American interests. The latter runs against the more fundamental objective of destroying the Islamic State. Nothing justifies allowing Ankara to drag NATO into a war with Russia.

Finally, Europe could, if it was so inclined, defend itself. Why, 70 years after the conclusion of World War II, are Europeans still dependent on America?

Why can’t an area with a larger economy and population than the U.S. provide its own soldiers for defense? Why can’t an area of such economic prowess, which has around eight times the GDP and three times the population of its only possible antagonist, Russia, deter any threats?

The reason the Europeans don’t do so is because they don’t want to and don’t have to. Some don’t believe that Moscow actually poses much of a threat. Others figure only the nations bordering Russia face any risk, and there’s little interest in “Old Europe” for confronting Moscow over “New Europe.” And almost everyone assumes America will take care of any problems.

Particularly striking is the lack of military effort from those supposedly threatened by the supposed new Hitler to the east. Over the years American officials have pleaded, cajoled, contended, and begged the Europeans to do more.

To no effect. Reported Jan Techau of Carnegie Europe: “while European membership in NATO has nearly doubled since 1990, defense spending by Europeans has gone down by 28 percent since then.”

The U.S. should announce that the world has changed since creation of a U.S.-dominated NATO. It was time to refashion the alliance.

One possibility for the future would be a European-run NATO, with America perhaps as an associate member. Another alternative would be a continental defense run alongside the European Union. Maybe there’s something else.

But the time for subsidizing, coddling, and reassuring the Europeans is over. American taxpayers finally deserve at least as much consideration as European ones.