Five years ago I wondered ‘Why aren’t we more worried about the nuclear threat?‘ And three years ago I wondered ‘Is nuclear war more likely than you think?‘ Then just over two weeks ago this happened: Putin uses the nuclear threat and then he did it again when he put Russia’s nuclear forces on ‘special alert’.

So the question becomes Would Putin press the nuclear button? I’m sure everyone is pretty much thinking ‘no, because that would be unthinkable’ except that he has clearly thought about it. I agree with Tyler Cowan that the risk is still pretty low but it is not zero. Putin has said as much, “why do we need the world if Russia won’t be in it?” and when you’ve identified yourself with Russia then the calculation can quickly become ‘why do we need the world, if I’m not in it?’

The problem with nuclear weapons is that one day someone might decide to use them.