Big Story, No Access: Covering The North Korean Nuclear Test
"It's a story that's sort of doubly constrained," said national security correspondent David Martin. "Number one, you have a total lack of access to North Korea. And two, you're dealing with a story about two of the most secretive things, nuclear weapons and intelligence."
Essentially, there aren't a lot of sources to begin with and even the U.S. government doesn't necessarily have the best information about what happened. "So you just go into it knowing that those are the rules of the game," he said.
When North Korea announced that it had conducted a nuclear test, there was no objective information to work with. "So you rely on the people you've dealt with over the years," said Martin, "and they tell you the best information they have."
The inevitable problem: "you have to recognize that the best information may be inaccurate," said Martin, citing the intelligence community's past inaccuracies regarding the existence of weapons of mass destruction in Iraq. "When you think about how wrong the intelligence community was on that, then you really have to approach the story with caution."
One problematic element of the story, said Martin, arises in estimating the yield of the blast.
"No one is sure it was nuclear, but that's the working assumption," he said. However, he explained, determining the full yield of the blast is based on readings from a seismograph, the same method used in measuring an earthquake. "The catch is that to know what that number means on a Richter scale and how it translates into the power of a weapon, you have to know the geology of the earth," said Martin. An underground blast measuring 4.2 on the Richter scale would mean two different things if the ground was made of sand versus granite.
"We have lousy information on the geology," said Martin, which limits everyone's understanding of the impact of the blast. "You saw it on the first day. The Russians were saying it could have been anywhere from 5-15 kilotons, roughly the range of the bomb of Hiroshima. But U.S. intelligence was saying it was less than 1 kiloton. South Korea's estimates were in between."
In his story for the "Evening News" last night (you can watch it here) Martin reported the U.S.'s estimates on the yield of the blast – less than a kiloton. He went with the U.S. estimate "not because it's more accurate than the others, but because that's the information that the people who are making decisions are using."
Martin noted in the piece that the test was "something less than a total success." And in an interview, Former Assistant Secretary of Defense Ashton Carter, called the test "almost surely a failure."
Martin says that in using sources like Carter and other former intelligence officials, he is seeking people "who can listen to what the government is saying and help interpret it. They know better than I do how skeptical you have to be of these estimates."