Elleman, Michael

Abstract
The explanation for North Korea’s rapid progression in long-range missile technology is simple: it acquired a high-performance liquid-propellant engine from a foreign source.
North Korea’s missile programme has made astounding strides over the past two years. An arsenal that had been based on short- and medium-range missiles, along with an intermediate-range Musudan that repeatedly failed flight tests, has suddenly been supplemented by two new missiles: the intermediate-range Hwasong-12 and the intercontinental ballistic missile (ICBM) Hwasong-14. No other country has transitioned from a medium-range capability to an ICBM in such a short time. What explains this rapid progression? The answer is simple. North Korea acquired a high-performance liquid-propellant engine (LPE) from a foreign source.
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