With a Tweet, President Trump recently declared, “the United States must greatly strengthen and expand its nuclear capability”. He separately expressed his desire to see the US at the “top of the pack” in nuclear weapons. Trump is right on the numbers – the US is currently second to Russia, which possesses approximately 7000 nuclear warheads, down from some 40,000 in 1985. The US’s own arsenal numbers 6800 warheads, down from a peak of approximately 27,500 in 1975. But Trump’s comments take no account of the quality and sophistication of those warheads, and they run contrary to decades of nuclear disarmament. It remains unclear how many times over the US should be able to destroy the world to be ‘top’ in Trump’s books.