North Korea's test of a possible hydrogen bomb has escalated regional tensions, with South Korea and the United States discussing ways to deploy strategic military assets on the peninsula, and ally China's disapproval becoming ever more pronounced.
While analysts in the US and South Korea doubt the explosion was thermonuclear, South Korea's response has been particularly robust, hardly surprising given its capital Seoul is within easy striking distance of North Korea and would bear the brunt of any initial assault.
The message from Pyongyang has bounced between hailing the device as the “H-bomb of justice” and pledging that North Korea would act as a responsible nuclear state and would not to use its nuclear weapons unless its sovereignty was infringed.
Sabre-rattling from both sides is par for the course, but the rhetoric is taking on a new edge, and what is unusually baffling about the tests is how North Korea seems prepared to completely isolate itself internationally, including its sole major ally, China, over its nuclear programme.
As in previous tests, China was not given prior notice, although it is Chinese money that is largely propping up North Korea's flagging economy. Japan was also furious, and prime minister Shinzo Abe phoned US president Barack Obama to call for a firm global response.
What irks China particularly is that it is put into a position where it has to support opposition to North Korea, even though it is keen to support the communist nation as a buffer against US influence on its borders.
South Korea’s defence minister Han Min-koo said the country’s military was exploring various options and, as one of its first steps, Seoul said it would resume propaganda broadcasts at the heavily fortified border between the two countries that has long infuriated the North.
38th Parallel
The battery of speakers along the 38th Parallel dividing the Korean peninsula blares news of South Korea’s booming economy, plenty of high-energy K-Pop music and critical commentary about the Kim dynasty that rules the North.
Mr Han said South Korea and the US "were on the same page" in condemning the test, and that Seoul would push for the early installation of its Kill Chain and Korean Air and Missile Defence (KAMD) to guard against threats from North Korea.
While making his comments, Mr Han was flanked by US Forces Korea commander Gen Curtis Scaparrotti and joint chiefs of staff chairman Lee Sun-jin.
What has rattled nerves in the region is the North Korean assertion that it was capable of miniaturising the H-bomb, which in theory would allow it to be placed on a missile and be within reach of South Korea, Japan and even the US west coast.
Mr Obama has spoken to President Park Geun-hye of South Korea to discuss options. Among the options they are examining are more sanctions and more weapons on the border.
South Korea does not have any nuclear weapons of its own, and the US removed tactical nuclear missiles from the South in 1991. US involvement could include nuclear-powered submarines, F22 Stealth combat fighters and B52 bombers.
Military escalation
After North Korea’s third test in 2013,
Washington
sent a pair of nuclear-capable B2 Stealth bombers on a sortie over South Korea in a show of force, which prompted North Korea to threaten the US with a nuclear strike.
"Any escalation in this region, any over-reaction can easily lead to not only a conflict between South and North Korea, but drag China and the United States and Japan into a confrontation," Anthony Cordesman, a defence policy expert at the Washington-based Centre for Strategic and International Studies think tank, told the Yonhap news agency.
The most likely step is an expansion of sanctions against North Korea. The UN Security Council has said it would work immediately on significant new measures against North Korea. However, sanctions at the moment are far from comprehensive, and it remains an open question whether the security council is ready to launch a full-on economic embargo, which would most likely meet with huge opposition from China.
Request to China
That said, China is also becoming increasingly irate about the test. A long-time ally which fought side-by-side with North Korea during the Korean War (1950-1953), China has been formally asked by South Korea to help issue “substantive and effective” punishments against North Korea for its fourth nuclear test.
There is widespread awareness in China that the nuclear test happened without the blessing of President Xi Jinping, and many people want to cut loose the country formally as “close as lips and teeth”.
"If North Korea keeps doing such tests, it will hurt social stability in these Chinese regions, posing a big challenge to the Chinese government. Pyongyang must consider the long-term negative impact on Beijing-Pyongyang ties and its own development," said the Global Times.
This, of course, does not mean that China is prepared to assume the role that US presidential hopeful Donald Trump sees, where China is left to deal with a major problem on its own doorstep without US intervention.
The China Daily said it would be "extremely wrong if the US thinks it can just stand by and exploit the deteriorating ties between China and North Korea".
