"Drones, Silos and Driving Missiles: North Korea Is Showing Its Nuclear Muscles with New Techniques" by Anne ter Rele for Trouw

"Yet it is more than just psychological warfare, see Tianran Xu of Open Nuclear Network, an Austrian NGO that committed to disarmament. 'It is also a military choice: Kim Jong-un wants to diversify his missiles to defeat his enemies to surprise.'
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Whether North Korea would really use nuclear weapons, like Kim does now threatens? It would be 'a miscalculation,' Xu thinks. 'Because if North Korea does, and the US responds with nuclear weapons, means the end of the Korean region. The US also knows that North Korea is kind of bluffing.' ... 'just like his daughter is growing up now. Nuclear threat is part of her reality - that can be a danger in the long run.' "