When it comes to the war in Iraq and other foreign-policy issues, Republicans like to harken back to the stalwart presidents of the Cold War. John McCain has invoked Harry Truman and Ronald Reagan as kindred spirits, and so has George W. Bush. Which raises the question: Why do they embrace those leaders while rejecting their policy?

The centerpiece of the U.S. approach to the Soviet Union was captured in a famous 1947 essay by American diplomat George Kennan, who rejected either war or retreat in favor of "a long-term, patient but firm and vigilant containment of Russian expansive tendencies."

Some conservatives, regarding this as appeasement, advocated "rollback" to liberate captive nations from oppression. But even resolute anticommunists like Dwight Eisenhower and Richard Nixon saw that the risks and costs were too high. They kept troops to guard western Europe, built a robust nuclear deterrent and employed prudent measures to block Soviet expansion. That was containment.

But in the months before the Iraq war, it became a dirty word. "Containment is not possible," President Bush insisted, "when unbalanced dictators with weapons of mass destruction can deliver those weapons on missiles or secretly provide them to terrorist allies." The only remedy for such regimes lay in pre-emptive war. McCain agreed, saying the only option in Iraq was "disarmament by regime change."

Amid all the war hysteria, it was easy to forget that containment worked against Stalin and Mao -- both unbalanced dictators with nuclear weapons. They were far more formidable tyrants with dreams of world domination. Yet we managed to preserve our security without preemptive war.

For that matter, containment had worked against Saddam Hussein. In the 12 years after the first Gulf War, we kept him in a box, where he was no threat to us or his neighbors. In 2002, he even had to accept the return of United Nations weapons inspectors -- who found no weapons of mass destruction because, thanks to our efforts, he had none.

But as Yale foreign-policy scholar Ian Shapiro noted in his 2007 book "Containment: Rebuilding a Strategy Against Global Terror" (just published in paperback), the Bush administration was dissatisfied. One reason was its unfounded certitude that Hussein had weapons of mass destruction. Deputy Defense Secretary Paul Wolfowitz also complained that containing Iraq had cost a staggering $30 billion over those 12 years.

Today, that sounds like a bargain. The long-term cost of the Iraq war, according to an estimate by Nobel Laureate economist Joseph Stiglitz, will exceed $3 trillion -- or 100 times the cost lamented by Wolfowitz.

Ronald Reagan took a different approach. In response to the Soviet invasion of Afghanistan, he continued President Carter's covert aid to the rebels but didn't send American troops. Likewise when a pro-Soviet regime gained power in Nicaragua. The key to containment was finding affordable means to constrain and weaken the enemy, without bleeding ourselves down in wars we didn't have to fight.

Our policy in Iraq has been just the opposite. And Iran could be the next mistake. McCain says Tehran cannot be allowed to acquire nuclear weapons -- which implies he would go to war to prevent it, no matter what the price in blood or treasure.

The claim is that the Iranians are too crazy to be deterred from using nukes against Israel or giving them to terrorist groups to use against us. One common trait of governments and their leaders is an overriding desire to survive. If Iranian nukes are ever used for aggression, the regime can be sure Iran will be, as Hillary Clinton so vividly put it, "obliterated."

Shapiro told me he sees no evidence that Clinton or Barack Obama would return to containment. But the challenges we face are likely to push them toward it. Those dilemmas, after all, have prompted a reconsideration by none other than President Bush.

One member of the Axis of Evil, North Korea, has acquired a nuclear arsenal. Instead of launching a preemptive strike, the Bush administration has chosen to 1) live with it if we have to, 2) negotiate with Pyongyang to give it up, and 3) maintain strong defenses in South Korea.

That route is plainly the least bad option toward North Korea. But don't dare call it containment. And don't get the idea it could ever work anywhere else.

Steve Chapman's column is distributed by Creators Syndicate.