Scared about North Korea? You aren’t scared enough

TH: Having an ICBM is one thing, having a miniaturized nuclear warhead to put on it is another. Kim has bragged about mastering the technology, and released a (unintentionally hilarious) propaganda photo of himself standing next to their supposed device. Do you think he’s lying? If so, how close are they?

JL: I don’t have any doubt that North Korea has a compact fission device that fits on a ballistic missile. North Korea has conducted five nuclear tests –- and if we look at the other nuclear powers, after five nuclear tests they were all capable of building compact nuclear weapons and/or well on their way to thermonuclear weapons. To go back to my point about China, the U.S. expressed the same skepticism about whether China could make a compact device small enough to fit on a missile. The Chinese responded by altering their nuclear test schedule so that their fourth nuclear test, in 1966, was a test of a live nuclear warhead on a real missile, which they fired across their country. The Chinese made their point. I hope the North Koreans doesn’t feel the need to do something similar and fly a nuclear-armed missile over Japan…

TH: Experts say that if the ICBM was put on a more traditional angle, it could have flown 4,000 miles as opposed to the 600 or so it went before falling into the Sea of Japan. That would put all of Alaska in range if true. But you wrote the other day in the Daily Beast that it could possibly bring the continental U.S. into play as well. Tell us why, and whether the U.S. is taking that threat seriously enough.

JL: Well, there is a difference between the range the missile demonstrated last week, which was about 4,000 miles, and what the simulations we do at the Middlebury Institute suggest the missile may be capable of. My colleages, along with David Wright at the Union of Concerned Scientists, looked very closely at the launch of a new intermediate-range missile in May, as well as this one, trying to measure the missile and model its performance. It seems to me the North Korea cut the engines a bit early here, possibly so they did not overfly Japan. But they have been very clear their targets are in the continental U.S. — the Pacific Fleet in San Diego, Washington, and lately New York City — not Alaska. And our initial modeling of this missile suggests that it should be able to deliver a nuclear-weapon sized payload to most, if not all, those places. We’re still modeling away though.