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The proof-of-concept plutonium pit for the next-generation intercontinental ballistic missile warhead is still on the slate for fiscal year 2023, but cranking out 30 copies annually just three years after that will be “challenging,” the director of the world’s first nuclear weapons lab said last Friday. But “I would rather push to a timeline that is challenging,” Thomas Mason, the Los Alamos lab director, said in an online forum hosted by the Advanced Nuclear Weapons Alliance and the Mitchell Institute…
