This Monday greeted North Korea watchers with a one-two punch: an analysis by IISS Senior Fellow for Missile Defence Michael Elleman, plus a companion article in the New York Times, positing a connection between North Korea’s new and powerful rocket engines and Ukraine’s space-launch industry.

The gist of Elleman’s thesis was that engines powering both North Korea’s Hwasong-12 intermediate-range ballistic missiles, or IRBMs, and the first stage of its Hwasong-14 intercontinental-range ballistic missiles, or ICBMs, could not have been produced in North Korea.

He judged them, instead, to be modified RD-250 engines, originally designed and built in the Soviet