North Korea's nuclear chest-beating has achieved the seemingly impossible by aligning the concerns of South Korea, Japan and even China, three Asian neighbors that have a long history of strained ties.
While all those countries have separate aims and interests, they share with the United States a mutual interest in containing the North Korean regime, restraining its rhetoric and keeping Pyongyang's nuclear option in a box, says Richard Bush III, the director of the Center for Northeast Asian Policy Studies at the Brookings Institution.
"One charming thing the North Koreans possess is an ability to drive others closer together," he says.
North Korea in recent weeks has threatened the United States, South Korea and Japan with annihilation, and its nuclear and missile tests have been carried out in defiance of Beijing's warnings.
International condemnation has been fierce, aside from former NBA star and recent visitor Dennis Rodman, who declared his admiration for leader Kim Jong Un. "I love the guy. He's awesome. He's so honest," Rodman told ABC.
North Korea's recent behavior prompted Elizabeth Cobbs Hoffman, a professor of American foreign relations at San Diego State University and a national fellow at the Hoover Institution, to write in The New York Times that "China, Japan and South Korea should be encouraged to rank this problem No.1."
North Korea's saber-rattling is heard loudest just south of the Demilitarized Zone. Memories of the the Korean War are never far from the surface, and are periodically refreshed by events such as a 2010 torpedo attack on a South Korean ship that killed 46 sailors. Pyongyang followed up that attack by shelling the South Korean border island of Yeonpyeong.
South Korea's president at the time of the 2010 sinking, Lee Myung-bak, was criticized for his perceived weak response.
"I think that the North thought that the sinking of the South Korean ship was a huge victory, because all South Korea did was sit there and wring its hands and appeal for international investigations and assistance," says George Lopez, a political science professor at the University of Notre Dame who served as a U.N. monitor for sanctions on North Korea.
Bush says, "After those two incidents in 2010, the South Koreans decided they were responding too passively and that if there were future attacks, they would respond much more vigorously."
South Korea's new president, Park Guen-hye, hoped to steer a middle path between the country's hawks and doves. Instead, "she [was] met, even before her inauguration, with unusually bellicose rhetoric from the North," says Robert Hathaway, the director of the Asia Program at the Wilson Center.
"It's partly because she's a brand new leader and partly because she's a woman," he says, adding that Park has "very compelling domestic political interests not to appear weak."
If there was any question that Pyongyang would make full use of the gender card, Wednesday's remark by the North blaming tensions on the "venomous swish" of Park's skirt, should put it to rest.
According to Lopez, most South Koreans are concerned about another artillery bombardment — like the one in 2010 — rather than a nuclear strike or a Korean War-style ground invasion.
"If the South were to retaliate, it would likely be some kind of a selected strike against some target in the North with the full understanding that it could lead to a larger conflict," says James Auer, director of the Center for U.S.-Japan Studies and Cooperation at the Vanderbilt Institute for Public Policy Studies.
"If the North Koreans attack, they are definitely tempting fate, not knowing how the new South Korean leadership will respond," Auer says.
In the longer term, Pyongyang's claim of long-range missiles that can reach the United States could punch a hole in the U.S. nuclear umbrella that shields not only South Korea but Japan as well.
For Seoul, it "calls into question their whole security strategy," the Brookings Institution's Bush says.
That fear has pushed Washington and Seoul toward a joint missile defense system based in South Korea and aimed at handling a limited missile strike from the North.
For Tokyo, Pyongyang's burgeoning nuclear and missile capabilities, rather than its conventional forces, are the paramount worry. Japan is easily within range of the generation of ballistic missiles that North Korea is currently testing.
Japan hopes its own missile defense system, developed jointly with the U.S., would be enough to protect it from a North Korean first strike. Tokyo has also made clear that it is prepared to intercept any North Korean missile launch overflying its territory.
So far, Pyongyang has been careful to avoid Japanese airspace.
"If they took down a missile, there would be very little objection to it other than from the North Koreans," Auer says.
Japan, the first and only country to be hit by atomic weapons, has foresworn a nuclear option thus far, but North Korea's provocations have re-energized an ongoing debate on the subject.
Tokyo "has the know-how and the technical abilities" to go nuclear, the Wilson Center's Hathaway says. "The only thing missing, presumably, is the political decision to move forward."
Hathaway says he doubts that Japan would make such a decision anytime soon, but, according to Bush, every time in the past half-century that there has been a major strategic shift in Northeast Asia, "the Japanese have at least considered privately whether they should have nuclear weapons."
China's relations with North Korea are a much grayer area than for Japan or South Korea. But, like Seoul, Beijing was indelibly colored by the Korean War.
In 1950, Chinese troops crossed the Yalu River border with North Korea as part of a rear-guard action to save the North from imminent defeat. Since then, China has remained a more or less stalwart ally of Pyongyang.
"To this day, China has seen the value of having North Korea as a buffer between it and South Korea and the United States," says Bush of Brookings. "It became worried after [Kim Jong Il] had his stroke in 2008 that the North Korean regime was becoming very unstable, potentially. So, it became even more indulgent of North Korea. When you issue a blank check to your ally, your ally is likely to cash the check, and that's what we've been seeing."
But there are signs of a "growing irritation" with North Korea, Hathaway says.
After Xi Jinping became head of the Chinese Communist Party last fall, one of Beijing's first moves was "to warn publicly North Korea not to engage in further provocations," he says.
North Korea went ahead in December with a satellite launch that doubled as a thinly veiled test of an intercontinental ballistic missile.
The Obama administration has already committed to a strategic "shift to Asia," and Pyongyang's shadow boxing has only strengthened its hand in a region that Beijing views as its own backyard — although China's own actions have also done plenty to bolster the region's desire for an expanded U.S. presence
Lopez says part of the problem is that the Chinese leadership just doesn't like North Korea's style.
China "is very good at lining up the costs and benefits of various acts and strategic relationships," he says. "The pragmatism on the Chinese side and the lack of it in North Korea bothers them."