A Google Map view of North Korea’s suspected nuclear test site, based on USGS data from the resulting earthquake, is indicated at the green arrow. The red button shows the suspected site of North Korea’s nuclear facility. (Screenshot by Washington Post)

Within hours of the North Korean nuclear test this week, the UN security council was meeting in emergency session. But how dangerous is this development, and what is likely to happen next? James Blitz, diplomatic and defense editor, Christian Oliver, former Seoul correspondent, and Simon Mundy, the current FT correspondent in Korea, join Gideon Rachman.

North Korea test: Financial Times Audio Analysis  Feb 13, 2013  6:35 pm

In his first reaction to the new test, STRATFOR Global Intelligence underlined the yet unknown sort of device N Korea had tested.

1. Initial estimates suggest a 6- to 7-kiloton yield, which is slightly larger than past North Korean tests. Prior to the test, it was suspected that the North would test a uranium device as a follow-on to its two earlier plutonium tests.
2. Although Pyongyang has pursued a strategy of survival based on presenting a fearsome, irrational yet weak image, the North views its nuclear and missile program as more than just a bargaining chip.
3. By keeping the program seemingly viable but ambiguous (underground tests, space launches, but no proof of weaponized nuclear warheads and effective long-range ballistic missile guidance systems), Pyongyang is seeking deterrence while trying not to trigger military pre-emption.

 The most delicate question in the first few hours after the test was what type of nuclear material had been used, if it was plutonium of highly enriches uranium. The difficulty to get a clear answer reminds us the country’s hability to control what the rest of the world knows and does not know about what is going on inside North Korea.

 As Max Fisher explained in The Washington Post, the question matters, and for more than just East Asia.

North Korea has previously used only plutonium in its bombs, but if it’s now detonating uranium, that would be bad news for four reasons:

1. North Korea would have two ways to build a bomb, which means a potentially larger arsenal.
2. The country has a natural supply of uranium and can enrich to bomb-making levels in secret; plutonium is limited and is much tougher to hide. So its weaponized uranium would be tougher to keep track of and easier to make in larger quantities.
3. Iran uses uranium in its nuclear program, so North Korea could share research and lessons from the nuclear test with Tehran.
4. Uranium is easier to ship abroad, meaning North Korea could more easily sell it.