Transcript for This day in history: Oct. 9, 2006

North Korea set off an underground explosion overnight that it claims was a nuclear test. And all of a sudden. A country that the US administration considers part of an axis of evil. With a leader that many in the world considered peculiar and dangerous was it would seem un nuclear power. We cover that story from the Pentagon the White House and the Korean Peninsula tonight beginning. With our national security correspondent Jonathan Karl. Yeah. With a few words shock wave sits around the world. The nuclear test North Korea announced is in historical event it has brought our military and our people huge joy. Put it brought only fear in condemnation from the rest of the world outlets such a claim itself constitutes a threat to international peace and security. United States condemns this provocative act. From the North Korean ambassador to the UN no apologies. I'm very much proud. Bob Wallace signed Houston voters said yes we have conducted such a very that if successful are you there underground test. We anymore. Thank you did I do and they saw. Tonight officials are still trying to figure out what exactly North Korea did. The US and its allies have planes in the area searching for signs of radiation. They know something happened seismic graphs measured a blast registering four point two on the richter scale the size of a small earthquake. If it was a nuclear explosion in May have been something of a dud. US and South Korean officials say produced about one kill a ton of explosive power. By comparison the nuclear tests conducted by India and Pakistan in 1998. We're between four and twelve kill a tons. The real concern is what North Korea may do next could be arm a missile with a nuclear bomb just three months. North Korea tested several missiles including one with a projected range. Long enough to reach the United States this is definitely a crap and not an imminent threat they don't have a deliverable weapon the intelligence community is divided. About if and when North Korea could create a nuclear armed missile. The more immediate fear will North Korea sell its nuclear material on the black market. We should now think seriously about the possibility that north Koreans sells a nuclear bomb. Who al-Qaeda or some of them Bob that they bring that nuclear bomb to an American city and that we see a nuclear nine elevenths. And that proliferation concern is the thing tonight Charlie but US officials say if the thing that most worries them about North Korea. Just that you just mentioned there is some uncertainty. About what they did how assure our pentagon officials that this was indeed. A nuclear test. Well they aren't sure they won't be sure maybe for a few more days trolley but one senior administration official told me. Just a short while ago that the working assumption is that that was in fact a nuclear test. Although not a very successful. All right Jonathan Karl thanks reporting from the Pentagon the Bush Administration has taken a tough line with North Korea from the start. It was the president who said three years ago that the US would never tolerate. A nuclear armed North Korea but now the North Korea has crossed the line it was warned not to cross. The options may be limited. Our chief White House correspondent Martha Raddatz is joining us from the White House Martha. Charlie there really are just two options here or sanctions or military action and both are fraught with problems. Within twelve hours of the announced nuclear test the UN Security Council had condemned North Korea no one defended. No one even came close to defending. But no one is under any illusion that any of the options are good ones today's initial US response is a strong call for sanctions. The US circulated a draft resolution today that would prohibit trade of all military goods with North Korea. Prohibit financial transactions that could be used to support its proliferation activities. And authorize international inspection of all cargo to and from the country. But sanctions would weaken North Korea and their fears that a weakened North Korea would make it even more dangerous or lead to the country's collapse. One reason why China which provides millions of dollars of aid and does two billion dollars of trade with North Korea. Has long rejected sanctions but the last thing they need it's it's. Great giant. Refugee flow that causes them stability problems today both Russia and China denounced North Korea but it is by no means clear that they will support sanctions. As for the military option. Even surgical airstrikes on suspected nuclear facilities would pose serious problem. They're actual weapons are dispersed. In all kinds of locations deeply buried in tunnels and the like we can't in any realistic scenario assumed that we know the location. Of these particular assets nor can we have a high degree of confidence that we would take them out. But their real fear here with using any kind of military strike Charlie is that North Korea would respond with a false scale attack. On its neighbor to the south.

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