Deterring Kim Jong-Il

In an interview aired last week, George Stephanopoulos put the question to President Bush: What would he do if "North Korea sold nukes to Iran or al-Qaeda?" Bush replied, "They'd be held to account."

Seeking specifics, Stephanopoulos asked: "What does that mean?" The president answered, "I want the leader of North Korea to understand that he'll be held to account. Just like he's being held to account now for having run a test."

Say what? If  North Korea sells a nuclear weapon to Osama bin Laden or Iranian President Mahmoud Ahmadinejad, he should expect the United States to go to the United Nations and negotiate further sanctions? And if al-Qaeda sneaks that bomb into the United States and we awake to the president's nightmare in which a mushroom cloud engulfs Washington or Los Angeles, then what? If this formulation stands -- without further specification -- America risks becoming the victim of a catastrophic "deterrence failure."

Deterrence emerged as a central concept in Cold War strategy. It meant convincing the adversary that the costs of taking an unacceptable action would greatly exceed any benefits it could hope to achieve. How did the United States prevent the Soviets from seizing Berlin? By convincing Soviet leaders that such an attack would trigger a response that would destroy their country.

Effective deterrence required three components: clarity, capability and credibility. Clarity meant bright lines and unacceptable consequences. Credibility was understood to be in the eye of the beholder. How credible was the threat to trade Boston for Berlin? Never 100 percent. But U.S. forces, exercises and communication were crafted to convince Soviet leaders they dare not test it.

To date the Bush administration has demonstrably failed to deter Kim Jong Il. Successive U.S. demands that Kim not develop nuclear weapons, not test a missile and not test a nuclear bomb have been defied. In each case, the president has asserted that this would be "intolerable." Pressed to be precise about what this threat meant, however, Bush refused, responding instead, "I don't think you give timelines to dictators and tyrants." National security adviser Stephen Hadley has gone further, arguing that red lines make no sense in dealing with North Korea because "the North Koreans just walk right up to them and step over them."

Having stiffed Bush -- and the world -- in building a nuclear arsenal, testing a long-range missile and testing a nuclear weapon, might Kim now imagine that he could also sell nuclear weapons?

America's challenge is to prevent this act by convincing Kim that he will be held accountable for every nuclear weapon that originates in North Korea. This requires clarity, credibility about our capacity to identify the source of a bomb that explodes in one of our cities (however it is delivered by whomever) and a believable threat to respond.

Kim must be convinced that American nuclear forensics will be able to identify the molecular fingerprint of nuclear material from his Yongbyon reactor. He must feel in his gut the threat that if a nuclear weapon of North Korean origin explodes on American soil or that of a U.S. ally, the United States will retaliate precisely as if North Korea had attacked the United States with a nuclear-armed missile: with an overwhelming response that guarantees this will never happen again.

Here, the president can take a page from President John F. Kennedy in the Cuban missile crisis. In 1962, as the Soviet Union was emplacing nuclear-tipped missiles in Cuba, some worried that these weapons could be transferred to a young revolutionary named Fidel Castro. Kennedy issued an unambiguous warning to Nikita Khrushchev. "It shall be the policy of this nation," he announced, "to regard any nuclear missile launched from Cuba against any nation in the Western Hemisphere as an attack by the Soviet Union on the United States requiring a full retaliatory response upon the Soviet Union." Khrushchev knew that meant a nuclear war.

The writer, an assistant secretary of defense under President Bill Clinton, is director of the Belfer Centerfor Science and International Affairs at Harvard's Kennedy School of Government and the author of "Nuclear Terrorism: The Ultimate Preventable Catastrophe."