North Korea conducted an underground nuclear test on Tuesday, prompting President Barack Obama to call the detonation of a miniature nuclear device a “highly provocative act” that threatens U.S. security and international peace. It is the third nuclear test by Pyongyang since 2006 and is escalating concern that the isolated Stalinist state is now closer to building a bomb small enough to be fitted on a missile capable of striking the United States and its allies. The test was conducted hours before Obama’s annual State of the Union speech.

North Korea’s official Korean Central News Agency said the test was conducted, “in a safe and perfect way … with the use of a smaller and light A-bomb, unlike the previous ones, yet with great explosive power.” The statement said the nuclear device did not impose “any negative impact” on the environment.

North Korea said the atomic test was merely its “first response” to what it called U.S. threats and said there would be unspecified “second and third measures of greater intensity” if the United States remains hostile to the North. Washington had led the call for more U.N. sanctions against Pyongyang after the North launched its first rocket and put a satellite into obit in December. While the North said the launch was for its civilian space program, the Obama administration believes it was part of a covert program to develop ballistic missiles that can carry nuclear warheads.

We ask two Stanford experts on North Korea to weigh in: David Straub, the associate director of the Korean Studies Program at the Walter H. Shorenstein Asia-Pacific Research Center (APARC), and Nick Hansen, an affiliate of the Center for International Security and Cooperation who is an expert in foreign weapons systems.   

Q. Why conduct the test now?

Straub: Since the two previous North Korean nuclear tests took place on American holidays and the North Korean themselves have announced that their moves are "targeted" at the United States, many observers have concluded that the this test was especially timed to coincide with President Obama's State of the Union address. It is also possible that, as others have speculated, the North Koreans also took into account that Feb. 16 is the birthday of North Korean leader Kim Jong Un's father, Kim Jong Il, the man who is said to have instructed North Koreans to proceed with the nuclear weapons and missile programs. Others have speculated that the North Korean leadership wanted to test the device before the Feb. 25 transition in South Korea from the current president Lee Myung-bak, to the president-elect, Park Geun-hye. The timing could be intended to punish Lee, whom the North Koreans say they despise, while, the argument goes, making it a little easier for Park to reach out to the North before her inauguration.

Q. What message is North Korea’s young and relatively new president, Kim Jong Un, trying to send to the world with this test?

Hansen: Kim seems to be saying: I’m going to do what I say I’m going to do – and nobody is going to dissuade me. The North said they were going to launch a satellite, and by God they did. They said they were going to touch off a nuclear test after that, and by God they did. Now we have to wait and see what’s next.

Straub:  The North Koreans themselves are saying that the test is a response to the military threat posed to it by the United States and to U.S.-led UN sanctions imposed on North Korea after its rocket test in December. The North Koreans have complex motivations for pursuing nuclear weapons. Many North Koreans may actually believe that having nuclear weapons will defend them against the United States. But the fact of the matter is that the United States and South Korea have never attacked North Korea over the decades, while the North Koreans have repeatedly attacked South Korean and American targets, most recently killing 50 South Koreans in 2010. North Korea's top leaders see nuclear weapons and missiles as a panacea. Fearful of opening up to the outside world because of the lies they have told their people, Pyongyang wants to believe that it will eventually maneuver the United States and the international community as a whole into accepting its possession of nuclear weapons and forcing the removal of sanctions against it. That won't happen, but even if it did, it would not resolve Pyongyang's basic problems, which stem from the totalitarian nature and history of its regime.

Q. What concerns you most in the wake of this test?

Hansen:  The thing I’m worried about now is that they also said they’re going to launch more satellites and long-range missiles. They displayed one in the military parade of 2010, an intermediate-range missile that can probably go 2,000 miles. When you think about that, 2,000 miles, or maybe a little bit longer, it puts just about every U.S. base in Asia under its threat, including Guam, Okinawa, Taiwan and everything in Japan. It’s a threat if they could put a warhead on it. The KN-08 is a bigger, three-stage rocket and is more of a threat, with the potential of hitting at least Alaska, Hawaii and maybe the U.S. West Coast. But remember, the North has tested neither.

Q. The test was in defiance of Pyongyang’s chief ally, Beijing, which had urged Kim not to risk confrontation and said the North would “pay a heavy price” if it proceeded with a test. How will China respond?

Straub: China is key in dealing with the North. China provides North Korea with most of its external support, including vital food and energy supplies. Chinese leaders are certainly not happy with their North Korean counterparts, as China would prefer peace and stability in the region, so it can focus on its own economic development. But Chinese leaders are fearful that putting a great deal of pressure on North Korea might result in chaos, with unpredictable and possibly very dangerous repercussions for China and the region. Thus, before North Korean nuclear and rocket tests, typically the Chinese press Pyongyang not to proceed. But immediately after a test, the Chinese begin to urge "all parties" to exercise restraint. In the United Nations, where China has a veto on the Security Council, it reluctantly agrees to the minimum condemnations of and sanctions against North Korea. After the dust settles, however, China doesn't seriously implement the sanctions. In fact, since North Korea conducted its first nuclear test in 2006, Chinese trade with North Korea has dramatically increased as a result of a PRC government decision to support North Korea. China may agree to a stronger resolution this time, but ultimately this pattern will almost certainly repeat itself.

Q. The North Koreans have said the test poses no risks to the environment or its people. Is this accurate?

Hansen: It takes a while for the particles that are released from the test to get released from the cracks in the rock and get into the atmosphere. My guess is that because of this very hard rock, they probably don’t have much of a radiation release problem. It probably will just seep through naturally and should not be of any danger. Engineers seem to have done a good job from a security and safety standpoint; the way the tunnels make right-handle turns and then there are the blast doors and piles of dirt to soak up any release.

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