The vivid prospect of a North Korea with enough plutonium for six or eight bombs could prompt neighboring countries to consider building their own nuclear arsenals, security experts warn.
Moreover, it could mean that North Korea by mid-decade would begin exporting plutonium to an eager global black market, a threat that policy analysts say could not only destabilize East Asia but also encourage nuclear aspirants in the Middle East and other regions.
"We could be approaching a nuclear tipping point," said Mitchell Reiss, dean of international affairs at the College of William & Mary in Williamsburg, Va.
"What we're concerned about is whether it's going to start a nuclear chain reaction" in which previously nonnuclear countries "may start to reconsider their bargain and to hedge their bets," he said. "If you see North Korea acquire even a small nuclear arsenal, they may begin to wonder whether nonproliferation is a mug's game."
While Japan, South Korea and Taiwan are highly unlikely to decide to go nuclear any time soon, experts say, any of the three governments could probably build a nuclear arsenal within months or years should it decide that U.S. security guarantees are no longer enough to defend it against a more dangerous world.
Moreover, a nuclear North Korea would probably push all three nations to embrace missile defense systems, analysts say. That in turn could antagonize China, particularly if the U.S. sold such systems to Taiwan.
These and other scenarios have come under urgent discussion as policy analysts and North Korea experts voice growing doubt that the Bush administration strategy of pressuring North Korea to abandon its nuclear weapons program can succeed without the direct negotiations Washington has ruled out.
Next week's meetings between Assistant Secretary of State James A. Kelly and his South Korean and Japanese counterparts will probably include discussion of the still-vague plan for a compromise to be presented by South Korea's president-elect Roh Moo Hyun. It was unclear whether the mutual concessions Roh envisions to break the stalemate would satisfy North Korea that the Bush administration did not intend to try to topple Kim Jong Il once the U.S. finishes with Iraq, or avoid the moral hazard the Bush administration sees in rewarding North Korea with sweeter new deals when it breaks old promises.
The threat of nuclear proliferation in Asia makes China a pivotal player, experts say.
The Bush administration and the South Korean government are both courting China's help in persuading North Korea that a nuclear weapons program will make it a regional pariah. China has taken the unusual step of joining with Russia in publicly criticizing Pyongyang's nuclear program.
But China would be reluctant to punish its North Korean allies by reducing aid or trade, lest it worsen the already problematic flow of desperate North Korean refugees into northern China, said Gary Samore, a former National Security Council official now at the Institute for International and Strategic Studies in London.
However, analysts note that the United States used its influence in the 1970s and 1980s to stop Taiwan and South Korea from developing nuclear weapons.
Now, the Bush administration could argue that it's time for China -- the only country with leverage or influence over North Korea -- to do its part to keep the nuclear genie bottled.
If North Korea proceeds to separate the plutonium from its spent nuclear fuel rods, a precursor to making bombs, it would be crossing a "red line" with unpredictable consequences, experts agree.
Ever since North Korea declared it was restarting its nuclear program, the Bush administration has sought to downplay the dispute by arguing that the U.S. has long believed that North Korea might already have up to two nuclear devices. But that has caused more anxiety in Asia, not less, said Kurt M. Campbell, a former Pentagon official.
"The most alarming thing we've seen from the Bush administration is this, 'North Korea has two [nuclear weapons] and what's a few more?' type of approach," said Campbell, who is studying the "tipping point" scenarios with Reiss and North Korea specialist Derek Mitchell at the Center for Strategic and International Studies in Washington. "By saying it's not a crisis ... you are emboldening the North Koreans to go further and further."
Moreover, "North Korea could easily decide it wanted to put some of its plutonium on the black market, and they could get a handsome price for it," Campbell said. "Secondly, the other countries in the region have banked on a nuclear-free Korean peninsula. To have the U.S. basically blessing that [possibility of one or two North Korean nuclear weapons] creates all sorts of problems."
Japan is not "a screwdriver away" from making its own nuclear bomb, as some have asserted, Samore said. But it does have a ready supply of weapons-grade plutonium from its civilian nuclear reactor program, and the technological prowess to construct nuclear weapons probably in less than a year, he said.
Japan's peace constitution, its pacifist political culture, and its abhorrence of nuclear arms since Hiroshima and Nagasaki make it almost unthinkable that it would opt for nuclear weapons -- as long as the U.S. "nuclear umbrella" that protects it is viewed as secure.
South Korea does not have ready access to fissile material, and the United States has long opposed its building civilian nuclear reactors. China has warned that it might use force against Taiwan if the island developed nuclear weapons.
But that does not prevent those countries -- or any others -- from quietly preparing themselves in case other nations should opt out of the Nuclear Nonproliferation Treaty, as North Korea has threatened.
"The thing to watch is whether they try to develop dual-use facilities," such as Iran's advanced civilian nuclear power program, Samore said.
If North Korea decides to further escalate tensions, an obvious next step is to resume the missile tests it stopped during negotiations at the end of the Clinton administration.
North Korea has already tested both short- and long-range ballistic missiles -- and is suspected of swapping them with Pakistan for uranium-enrichment technology. Moreover, it has an established network of Middle East clients for its missile technology, and would find no shortage of buyers if it sought to earn hard currency by selling plutonium.
A resumption in missile testing could, in turn, trigger a stampede for missile defense systems in Asia, experts said.
Japan is already involved in joint studies with the United States on a sea-based missile interceptor, and last month stepped up its commitment to the research. The Japanese government stressed that it has made no decisions about deployment, however.
"If the North Korean missile and nuclear program proceeds without restraint, it makes it more likely that the Japanese will decide to deploy missile defenses," Samore said. South Korea and Taiwan might then clamor for similar technologies, and "the U.S. would have a hard time denying these to Taiwan," he said.
But China would view that as an unacceptable strengthening of the U.S.-Taiwanese security arrangement, Samore said.
Conservatives argue that North Korea's actions demonstrate the wisdom of the Bush administration decision to deploy missile defense technology.
The way to protect the existing security infrastructure is to develop the ability to shoot down incoming ballistic missiles, the delivery system of choice for nuclear, chemical or biological weapons, said Peter Brookes, a former defense official who is now head of the Asian studies program at the Heritage Foundation, a Washington think tank.
"We were fooled by India and Pakistan," which stunned the world by testing nuclear weapons in 1998, "and it could happen again," Brookes said. "Iran is pursuing a [nuclear] program, North Korea is pursuing a program, Iraq was pursuing a program. Despite our best efforts, we may be unable to prevent it. Therefore, missile defense is the logical next step."
Though many disagree with that view, the diagnosis that nuclear proliferation is undermining the global sense of security is widely shared.
In a 1963 speech, President Kennedy described his nightmare scenario of a world with up to 25 nuclear-weapon states. Reiss notes that the post-Cold War euphoria has now given way to an age of anxiety in which "new threats have arisen while the nuclear taboo was weakened."
The nuclear club now consists of seven nations: the United States, Russia, China, Britain, and France, which have signed the Nuclear Nonproliferation Treaty; and India and Pakistan, which have not. Israel, also not a signatory, is known to have nuclear weapons, though it has never acknowledged them.
A number of other nations, including South Africa and Ukraine, have voluntarily given up their nuclear weapons and joined the world nonproliferation regime.
Theoretically, any country can withdraw from the nonproliferation treaty after giving three months' notice -- as North Korea did in 1994 and has hinted it might again do.
"If all we were concerned about was North Korea with a few nuclear weapons, that would be bad enough, but deterrence and containment could work," said Reiss, a former National Security Council official. "It wouldn't be destabilizing, necessarily, to the region ... if it weren't for the threat that they would be an exporter. That makes all the difference in the world.
"President Kennedy's nightmare vision of a world with 15, 20 or 25 nuclear powers may yet come to pass," Reiss said.