North Korea's nuclear test Monday appears to have dashed hopes on both sides of the Pacific that Pyongyang was using its nuclear program as a bargaining chip with which to negotiate an end to its pariah status. Rather, diplomatic observers warn, North Korea's second test hardens suspicions that it intends to join the nuclear club permanently.
The brazen challenge, just weeks after the United Nations condemned a missile test, also illustrates how little effect international efforts have had in thwarting North Korea's intentions.
"It is looking more and more as if the nuclear program is something they intend to keep and they are not ready to bargain it away," says Denny Roy, a North Korea expert at the East-West Institute in Hawaii.
"We used to believe that North Korea was simply playing the nuclear card," adds Cai Jian, deputy head of the North Korea Research Institute at Shanghai's Fudan University. "Now we think it is a strategic choice."
North Korea exploded what the Russian military estimated to be a 10-20 kiloton nuclear device, significantly larger than its first test in October 2006 and comparable to the US bombs dropped on Hiroshima and Nagasaki.
The test was "aimed at strengthening its self defense nuclear deterrent in every way," Pyongyang's official KCNA news agency announced.
A few hours later, the North Koreans launched what appeared to be a short range surface-to-air missile.
Test may be fallout of a succession struggle
South Korean analysts were shocked more by the timing of the test than by the explosion itself, surprised by the speed which Pyongyang had organized it.
Domestic politics, rather than international factors, seem to be driving Pyongyang's behavior, a number of analysts suggest, even though North Korea said last month it was so angry at the UN condemnation of its April 5 missile test that it would resume nuclear activities and withdraw from six-nation talks aimed at denuclearizing the Korean peninsula.
Though outside observers caution that they have no way of knowing what is happening inside the secretive North Korean government as its leader, Kim Jong Il, believed to be battling ill health, two theories have emerged.
Alternatively, suggests Dr. Roy, Kim Jong Il is seeking crucial support from the military for his youngest son – tipped as a possible successor – and that "part of securing military support involves letting them ... move quickly to consolidate the nuclear program."
Mr. Kim may also hope that securing nuclear status for North Korea would draw Washington into bilateral talks. He "wants to be able to pass on a new relationship with the United States to his son, and that relationship is being recognized as a nuclear power," argues Ha Tae Keung, head of a radio station that beams news from Seoul into North Korea.
'An extremely thin band of options'
Whatever Pyongyang's motives, the nuclear test casts a heavy shadow over on-again, off-again six-party talks to persuade North Korea to abandon its nuclear ambitions in return for aid and an end to its diplomatic isolation.
"North Korea's first demand at any resumption of the six-party talks would be political recognition as a nuclear power," predicted Yan Xuetong, an international affairs expert at Beijing's Tsinghua University. If that were the case, "what will the six-party talks discuss if denuclearization is not a goal any more?"
"If they lower their goal from denuclearization to nonproliferation, their nature will have changed," Professor Yan added, in an online interview with Sina.com, a Chinese website.
US President Barack Obama reacted angrily to the test, which he said "warrants action by the international community." North Korea's efforts to develop a long-range missile and a nuclear warhead could potentially put Alaska within range of a nuclear attack.
The international community, however, has "an extremely thin band of options" in dealing with this threat, cautions Professor Kang, since Washington and other concerned capitals have made it clear they will not go to war over it.
"We are stuck with sanctions, pressure, rhetoric, and maybe some negotiations," Kang says.
From influential China, a mild rebuke
Sanctions, however, first imposed after Pyongyang's first nuclear test in 2006, have proven toothless, not least because neither Russia nor China has shown any enthusiasm for imposing them. Although Beijing said it was "resolutely opposed" to North Korea's test Monday, it issued only a mild rebuke, merely calling on the renegade nation to live up to its commitments.
China, North Korea's closest ally and the source of its fuel and much food, "is the only country in a position to really exercise tough and decisive pressure," says Roy. "But it is not inclined to do so because it fears the consequences of political instability in North Korea much more than the nuclear program."
"China faces a very difficult balancing act," says Professor Cai, "deciding how much pressure to put on North Korea without leading to a collapse" of the regime that could lead to chaos and to millions of refugees pouring across the border into China.
In the meantime, South Korean officials are bracing for possible incidents in the Yellow Sea – the scene of bloody battles between North and South Korean vessels in 1999 and 2002 – as Pyongyang seeks to show up Seoul's weakness.
• Donald Kirk contributed to this story from Washington.