"Fire it bravely for the Party and the motherland!" Kim wrote on his order, according to a photograph shown on North Korean state television on Wednesday, shortly the test of a new intercontinental ballistic missile called the Hwasong-15.
The test, North Korea's first since mid-September, allowed Kim to declare "with pride" that his country had "finally realized the great historic cause of completing the state nuclear force", one of the strongest statements yet on the status of his nuclear arsenal.
It came a week after U.S. President Donald Trump put North Korea back on a U.S. list of countries it says support terrorism, allowing it to impose more sanctions.
The test also follows a dramatic defection to South Korea by a North Korean soldier on Nov. 13, who braved a hail of bullets by fellow soldiers as he crossed the heavily fortified border dividing the two Koreas.
Neither the North Korean government nor its state media have made any mention of the defection, which dominated headlines in South Korea and in international media for days.
Analysts say the test makes technical sense for scientists trying to refine their rockets as they strive to achieve Kim's goal of developing a nuclear-tipped missile that can reach all of the U.S. mainland.
But the launch likely also had other benefits.
"They couldn't sit pat after having been designated a sponsor state of terrorism," said Kim Dong-yub, a military expert at South Korea's Kyungnam University.
The North Korean leader is also no doubt keen to fulfil a vow made in a 2017 New Year's message to soon achieve an operable ICBM, Kim said.
"Kim Jong Un said at the beginning of this year they were near completing their nuclear capability. Won't he have to say in next year's New Year's address that they've completed it?"
(Additional reporting by Christine Kim and Soyoung Kim; Editing by Robert Birsel)
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