Catalyst Fall 2017
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UCS Helps Interpret the North Korean Threat

Hwasong-12 missile

The Hwasong-12 missile, shown here in a North Korean military parade, has been tested twice recently in flights over Japan. UCS has been the go-to source for clear, reliable information about North Korea’s missile capabilities.
Photo: Kyodo News/Getty Images

By David Wright

Since the middle of last year, North Korea has conducted nearly 30 ballistic missile launches, culminating in a July test of a missile with the range to reach the US mainland. If you’ve read about these tests, chances are you’ve been informed by UCS analysis—we have been mentioned more than 10,000 times since May in press coverage of the North Korean nuclear tests.

Why does UCS analysis get so much attention? The short answer is that UCS has earned a reputation as an honest broker of technical information on this issue over nearly a quarter century. I began analyzing North Korean missiles in 1993 following an early test of its Nodong missile, which has the range to reach cities throughout Japan. In the years since, I have been part of a small community of nongovernmental experts who study these missiles’ capabilities and technology, as well as options for reducing the threat. This work has put me in contact with key reporters who follow North Korean launches and are looking for a reliable assessment of the missiles and the threat they pose.

One especially useful aspect of the analysis UCS provides stems from the fact that Pyongyang has tended to conduct its recent test launches on highly lofted trajectories. Launching in this way obscures the missiles’ military capabilities, but North Korea has done so for a practical reason: so the missiles will land in the Sea of Japan (at a relatively short distance from the launch site) without—until most recently—overflying Japan, which is seen as particularly hostile and reckless.

Based on early news and Twitter reports of the height and range of those lofted test trajectories, I use computer modeling to determine what range those missiles would have if flown on standard trajectories. Shortly after each test, UCS has posted this information on our blog,, and sent it out to reporters, providing the first public assessment of the range of these missiles. For the test on July 4, our assessment showed early on that the missile would have a long enough range to be categorized as an intercontinental ballistic missile (ICBM). This assessment contradicted initial statements by US intelligence, which reversed itself the following day and agreed that the missile was an ICBM.

By serving as an honest broker of technical information and calm, evidence-based analysis, UCS has earned the reputation as a go-to source for reporters. This, in turn, has provided us the opportunity to discuss options for responding to the tests—with diplomacy being the only realistic approach to addressing the problem of North Korea’s nuclear weapons capabilities.

David Wright, a physicist and leading expert on missile technology, codirects the UCS Global Security Program.