Without prompt, effective, leadership by the United States in response to the reported nuclear test by North Korea on October 8, two other consequences could follow: regionally, a nuclear chain reaction could take place in the form of an arms race, or, internationally, Iran could take a cue to be more provocative in the nuclear arena.

The most important thing is for the United States to take the lead in involving Japan, South Korea and China in very intensive diplomacy about how all of the major powers in Northeast Asia can avoid the temptation to engage in an arms race which will exacerbate fears of a nuclear confrontation in the region. Given that some people perceive that Japan's new leadership might wish to reconsider Japan's nuclear policy, it is vitally important that the United States lead an intense and sustained effort with Japan, South Korea and China to clarify each other's intentions and policies in ways that avoid any nuclear competition. These countries must take up the difficult task of determining what is the new objective toward North Korea -- is it to dismantle North Korea's nuclear weapons program, to limit the size of its arsenal, to limit its capacity to deliver its weapons on missiles, to prevent further proliferation of nuclear materials or technology to other states or terrorist groups, to isolate them further or to change the existing regime?

If it is concluded that the North Korean test was a technical failure, it is absolutely imperative that the United Nations Security Council take every step conceivable to prevent North Korea from testing again. As with its missile test, failure may make North Korea more determined to recoup its lost face by trying again. North Korea is a country that has chosen to isolate itself throughout most of its history. As a result, when it wants something from the United States and other countries, North Korea becomes incrementally more aggressive. It does the same when it also feels frustrated and threatened. This test is a signal of them wanting something and feeling frustrated.

China is a key actor because it provides the resources on which the North Korean elite depend for their own comfort. Stepped up efforts from the South Koreans and Japanese will be equally important as they will influence China's own calculations. Therefore, China, South Korea and Japan have to decide how hard they are willing to work to prevent North Korea from doing this again. The United States and China will have to work together to identify a common bottom line. With China's tough response and a restrained reaction from the United States, there may be an opportunity to do that as both parties move towards the middle.

As for the Iranian implications of the North Korean test, Iranian hardliners will be watching to see whether there is any effective international reaction against North Korea. It is crucial that Russia and China especially, due to their involvement in the North Korean talks and as veto wielding members of the Security Council, make sure that whatever signal is sent to North Korea is one that inspires caution within Iran.

Having calm, focused diplomacy thinking about the long-term is critical now. Working to build a cooperative front, and being careful to avoid knee-jerk Congressional action here in the United States, is vital to maintaining a constructive and effective course of action. The United States and other nuclear weapon states must pay more attention to steps they could take to prevent a chain reaction of other countries conducting nuclear weapon tests; now is the time for far-sighted, collaborative, and smart policies to prevent the further spread and use of nuclear weapons.