There are many things the US military badly needs these days. One thing it has no pressing use for is a new line of nuclear warheads being designed at America’s three nuclear weapons laboratories to replace the roughly 10,000 still on hand from the overbuilding frenzies of the cold war. This is a make-work project that risks triggering a new worldwide nuclear arms race. America should be focused on convincing nations like Iran and North Korea that such weapons will not enhance their security.

Pentagon planners and nuclear scientists keep trying to think up new uses for nuclear arms, from miniaturised battlefield weapons to large bombs designed to pulverise underground unconventional weapons labs. The other main argument put forward for designing new nuclear weapons concerns reliability.

That is a legitimate theoretical concern, but it has already been addressed. Since the Clinton era, US has lavished money on elaborate programmes. Since late last year, America’s nuclear labs have been instructed to design a new line of heavier nuclear warheads. This program sends a clear message to the rest of the world: now that the superpower arms race has ended, US see nuclear weapons as an important part of its military strategy. It should be no surprise if those nations conclude that they must develop nuclear weapons of their own. — The New York Times