When South Korean President Lee Myung-bak visited Washington for a summit with President Barack Obama on June 16, the United States reaffirmed its "commitment of extended deterrence" to Seoul, "including the US nuclear umbrella." In response, on June 25, the 59th anniversary of the outbreak of the Korean War, North Korea vowed to continue to expand its nuclear arsenal, to deliver a "fire shower of nuclear retaliation" in response to US "provocations," and insisted that the nuclear umbrella statement only "provides us with a stronger justification to have a nuclear deterrent."

    It is not entirely clear to us why the international community considers it wholly legitimate for the United States to say, "if North Korea engages in aggression against South Korea or the United States, we will retaliate with nuclear weapons," while it universally condemns North Korea when it says, "if the United States engages in aggression against us, we will retaliate with nuclear weapons." Perhaps, in light of all this radioactive rhetoric, it is worth pausing to consider just what "nuclear deterrence" might mean in today's world ... or whether it means anything at all.

    The conventional wisdom holds that nuclear weapons have only one legitimate function in today's world - deterrence. Most often this is framed as one country (the deterror) dissuading the use of nuclear weapons against it by another country (the deterree), by threatening nuclear retaliation in reply. This has long been the primary answer to the awkward question, just what are nuclear weapons for?

    Deterrence theory has sometimes also extended to deterring non-nuclear attacks. During the protracted Cold War, for example, the United States threatened nuclear retaliation in response to a hypothetical conventional Soviet attack on Western Europe - in an attempt to dissuade the USSR from launching such an attack. (Never mind that in historical retrospect that threat appears never to have been more than a phantom, used primarily to justify enormously bloated military budgets of our own.) The last US Nuclear Posture Review (NPR) under the Bush administration envisioned using nuclear weapons reactively in response to the use of chemical or biological weapons, proactively to prevent other countries from even acquiring such weapons, and unrestrictedly in the event of "surprising military developments" and "unexpected contingencies." And, indeed, the vague statements in this month's rhetorical nuclear exchange between Pyongyang and Washington leave somewhat unclear whether each party is intending to deter only nuclear aggression, or instead all aggression by the other.

    Like much conventional wisdom, however, it turns out that today, there just ain't much there there. We need to remind ourselves that "deterrence" is a high-falutin' term for basing one country's security on the threat to entirely incinerate another country, and all its inhabitants, and also making that country (and likely surrounding countries as well) radioactive and uninhabitable for generations to come. So deterrence theory is, to say the least, a morally shaky basis for a country's security. Nevertheless, for the sake of argument, let's say we can live with that moral quandary. Let's say that we just want to know whether or not deterrence "works."

    That brings us to the contemporary cases of both North Korea and Iran. If deterrence does work, then why should we care if North Korea keeps nuclear weapons, or if Iran gets nuclear weapons? Shouldn't the nuclear arsenals of the United States and Israel, vastly superior in both quantity and quality, deter North Korea or Iran from ever using nuclear weapons - against us or anyone else? If not, then just what are the more than 9,000 American and perhaps 200-400 Israeli nuclear weapons good for?

    As the prophet Edwin Starr might say, absolutely nuthin'.

    No international political issue received more attention during George W. Bush's second term than the possibility that Iran might acquire nuclear weapons. Today, still, few issues stand higher on Secretary of State Hillary Clinton's things to do list. Yet, a very simple question has rarely been asked. If Iran in fact acquired nuclear weapons, just what could they do with them?

    Indeed, it was Senator Clinton herself, during her 2008 presidential campaign, who arguably addressed that question most directly. Asked by an ABC News reporter in April how she would respond to an Iranian nuclear attack on Israel, she replied, "I want the Iranians to know that if I'm the president, we will attack Iran.... In the next 10 years, during which they might foolishly consider launching an attack on Israel, we would be able to totally obliterate them."

    However indelicate and unsubtle Senator Clinton's speculations might have been, it is difficult to dispute their validity. If Iran does in fact become a nuclear weapon state in the next few years, the "policy option" for Tehran of launching a sudden and unprovoked nuclear first strike, on Israel or anyone else, would result in certain and immediate destruction for the Iranian nation - and in certain and immediate death for the leaders who had initiated it as well.

    Sometimes the question of what Iran might actually do with nuclear weapons has been expressed in a single word. "If the Iranians were to have a nuclear weapon," said President Bush in 2006, "they could blackmail the world." He offered no elaboration or explanation of exactly what that might mean. Our American Heritage Dictionary defines "blackmail" as "extortion by the threat of exposure of something criminal or discreditable." Pay me money, or I'll reveal that you embezzled the community chest, or dispatched the leaky ferryboat, or seduced the farmer's daughter. What that has to do with the political utility of nuclear weapons is difficult to discern.

    Perhaps it meant that such a state might try to coerce another state by threatening a nuclear first strike. ("Evacuate the entire Israeli presence in the West Bank and East Jerusalem by next Thursday, or else.") But all existing nuclear weapon states already possess the capability to make such coercive threats. And yet, it is difficult to identify any historical instances where any of them have actually done so.

    Perhaps, instead, it meant that such a state might use its nuclear capability to persuade someone else not to do something. ("Don't send tanks across the Elbe, or else." "Don't try to change our regime, or else.") That's nuclear deterrence. Why that is considered legitimate geopolitical behavior in one case, but "nuclear blackmail" in the other, is also difficult to discern.

    Senator Clinton, in her April 2008 remarks, did not say that if Iran actually used nuclear weapons, the United States would necessarily have to employ its nuclear arsenal "to totally obliterate them." And she didn't need to. The United States, today, could do so completely with its conventional capabilities alone. When one includes such things as Department of Energy allocations for nuclear weapons (which, astonishingly, are not considered part of America's "defense budget"), veterans' benefits (which our children and grandchildren will still be paying to those wounded in Iraq and Afghanistan more than half a century from now), and the repeated "supplemental allocations," it becomes indisputable that the United States spends more on its military prowess than all the other countries in the world ... combined. That is a situation probably unprecedented in all of world history.

    And, however much those of us in the peace advocacy arena might deplore that reality, what it means today is that nuclear weapons have become militarily unnecessary for the United States. Any military mission that nuclear weapons can achieve for the United States can now be fully accomplished by its conventional weapons alone. That is true not only of Iran but also North Korea. There is simply no need for Washington to extend a "nuclear umbrella" over South Korea, because the United States can threaten North Korea with complete and utter destruction without any need to resort to nuclear weapons - and thereby hopefully deter North Korea from external aggression. To protect American national security, to defeat any enemy, and to dissuade any potential aggressor by threatening to inflict catastrophic retaliatory destruction upon it, America's conventional military power alone can fully do the job.

    Then there is the "what's good for the goose is good for the gander" conundrum. If the United States, despite its vast conventional superiority, still insists that it "needs" nuclear weapons to deter other countries from committing aggression against it, then why don't smaller, less well-armed countries need them as well? Especially countries like Iran and North Korea, which have legitimate concerns about having vastly superior military powers as neighbors.

    Consider the underlying credibility of the essential claim by the US - first to possess such overwhelming conventional military power, then to insist that even despite that it cannot protect American national security without also maintaining a vast nuclear arsenal, and then to haughtily instruct other states that despite their laughably smaller conventional military establishments, they should be fully able to protect their national security with these alone. Other states, which by any measure possess conventional military capabilities only a tiny fraction of our own (Iran, for example, spends on its military about one percent of what the US does), are told that they ought to be able to protect themselves from external threats with those forces alone. But we, with vastly greater conventional capabilities, maintain that we also must possess the nuclear hammer, or we will be unable to protect and defend ourselves.

    How could any other state possibly draw any other conclusion but one? If nuclear weapons serve to protect the national security of the mightiest country in the world, then surely they must be necessary to protect the national security of other countries as well.

    We want the scourge of nuclear weapons to be wiped from the face of the Earth forever. No nation should have them, not a single one. The human race must now get down to the hard business of negotiating the abolition of all nuclear weapons. That in the long run will be much more politically sustainable than the present reality - with nuclear weapons states hypocritically holding on to their own nuclear arsenals, while trying (and failing) to deny any nuclear weapons to anyone else.

    President Obama has repeatedly stated his commitment to provide leadership toward a nuclear weapons-free world. He reiterated his support for that goal in a stirring speech before a huge outdoor rally in Prague in April, saying, "Today, I state clearly and with conviction America's commitment to seek the peace and security of a world without nuclear weapons." Unfortunately, just a few sentences later, he felt compelled to add the caveat that a world free of nuclear weapons would likely not "be achieved quickly, perhaps not in my lifetime."

    The president is a young man, and for us, on this, too cautious. But he is not alone. Just last week, Russian Prime Minister Vladimir Putin stated, "If those who made the atomic bomb and used it are ready to abandon it, along with - I hope - other nuclear powers that officially or unofficially possess it, we will of course welcome and facilitate this process in every possible way." Putin is nobody's idea of a peacenik. However, there is no reason to believe he is just blowing hot air on this issue. Even if he were, it would cost Obama nothing to find out - by proposing negotiations on not just further nuclear weapons reductions, but complete elimination.

    Russia and the US are currently negotiating a "post-START" treaty to cut nuclear warheads to (probably) fewer than 2,000 each. However, they can and should go much further. We recommend that when President Obama visits Moscow next month, the United States and Russia announce that they intend to launch formal multilateral negotiations directed toward transforming the Nuclear Non-Proliferation Treaty (NPT) into a universal, verifiable and enforceable Nuclear Weapons Elimination Convention (NWEC). Such a convention would require the phased dismantling and destruction by a time certain of every nuclear weapon on Earth, prohibit thereafter the development, production, testing, deployment, stockpiling, transfer, threat or use of nuclear weapons, and impose strict controls with rigorous inspection provisions over all nuclear fuels and nuclear activities in every country in the world. Including ours.

    Just as common sense ain't too common, the conventional wisdom about the need to retain nuclear deterrence indefinitely apparently ain't too wise. The time to launch formal multilateral negotiations directed toward nuclear weapons abolition is now. Indeed, such negotiations could be commenced at the official 40th anniversary NPT Review Conference, scheduled to convene at the United Nations in May 2010. There is probably no other step that could simultaneously put us on the road toward strengthening the global non-proliferation norm, toward ditching nuclear weapons anywhere and everywhere, and toward ensuring that these abominations never return to haunt the affairs of the human race again.