"In 1877, Lord Salisbury, commenting on Great Britain's policy on the Eastern Question, noted that 'the commonest error in politics is sticking to the carcass of dead policies.'

"Salisbury was bemoaning the fact that many influential members of the British ruling class could not recognize that history had moved on; they continued to cling to policies and institutions that were relics of another era."

"Relics of another era" -- thus did Stephen Meyer, in Parameters in 2003, begin his essay "Carcass of Dead Policies: The Irrelevance of NATO."

NATO has been irrelevant for two decades, since its raison d'etre -- to keep the Red Army from driving to the Rhine -- disappeared. Yet Obama is headed to Brussels to celebrate France's return and the 60th birthday of the alliance. But why is NATO still soldiering on?

In 1989, the Wall fell. Germany was reunited. The Captive Nations cast off communism. The Red Army went home. The USSR broke apart into 15 nations. But, having triumphed in the Cold War, it seems the United States could not bear giving up its role as Defender of the West, could not accept that the curtain had fallen and the play was closing after a 40-year run.

So, what did we do? In a spirit of "triumphalism," NATO "nearly doubled its size and rolled itself right up to Russia's door," writes Richard Betts in The National Interest.

Breaking our word to Mikhail Gorbachev, we invited into NATO six former member states of the Warsaw Pact and three former republics of the Soviet Union. George W. Bush was disconsolate he could not bring in Georgia and Ukraine.

Why did we expand NATO to within a few miles of St. Petersburg when NATO is not a social club but a military alliance? At its heart is Article V, a declaration that an armed attack on any one member is an attack on all.

America is now honor-bound to go to war against a nuclear-armed Russia for Estonia, which was part of the Russian Empire under the czars.

After the Russia-Georgia clash last August, Bush declared, "It's important for the people of Lithuania to know that when the United States makes a commitment -- we mean it."

But "mean" what? That a Russian move on Vilnius will be met by U.S. strikes on Mother Russia? Are we insane?

Let us thank Divine Providence Russia has not tested the pledge.

For can anyone believe that, to keep Moscow from re-establishing its hegemony over a tiny Baltic republic, we would sink Russian ships, blockade Russian ports, bomb Russian airfields, attack Russian troop concentrations? That would risk having some Russian general respond with atomic weapons on U.S. air, sea and ground forces.

Great powers do not go to war against other great powers unless vital interests are imperiled. Throughout the Cold War, that was true of both America and Russia.

Though he had an atomic monopoly, Harry Truman did not use force to break the Berlin blockade. Nor did Ike intervene to save the Hungarians, whose 1956 revolution Moscow drowned in blood.

John F. Kennedy did not use force to stop the building of the Berlin Wall. Lyndon Johnson fired not a shot to halt the crushing of Prague Spring by Soviet tanks. When Solidarity was snuffed out on Moscow's orders in 1981, Ronald Reagan would not even put the Polish regime in default.

In August 1991, George Bush I, in Kiev, poured ice water on Ukraine's dream of independence: "Americans will not support those who seek independence in order to replace a far-off tyranny with a local despotism. They will not aid those who promote a suicidal nationalism based upon ethnic hatred."

Many Americans were outraged. But outrage does not translate into an endorsement of Bush's 43's plan to bring Ukraine into NATO and risk war with Russia over the Crimea.

Bush 43 bellowed at Moscow last summer to keep hands off the Baltic states. But his father barely protested when Gorbachev sent special forces into all three in 1991.

Bush I's secretary of state, Jim Baker, said it was U.S. policy not to see Yugoslavia break up. Bush 43 was handing out NATO war guarantees to the breakaway republics.

"Washington ... succumbed to victory disease and kept kicking Russia while it was down," writes Betts. "Two decades of humiliation were a potent incentive for Russia to push back. Indeed this is why many realists opposed NATO expansion in the first place."

Few Americans under 30 recall the Cold War. Yet can anyone name a single tripwire for war put down in the time of Dean Acheson or John Foster Dulles that we have pulled up?

Dwight Eisenhower, writes Richard Reeves, in his first meeting with the new president-elect, told JFK, "'America is carrying far more than her share of the free world defense.' It was time for the other nations of NATO to take on more of the cost of their own defense."

Half a century later, we are still stuck "to the carcass of dead policies."