Inever had much time for the Greenham Common women. As a mildly reactionary student of the 1980s, I regarded them – and their protest camp outside a British nuclear-weapons base – as silly and misguided. After all, decades of experience taught that nuclear deterrence worked.

Thirty years on and the nuclear peace is still holding. But I am becoming a little less secure in my belief that nukes will never be used.

There are three reasons for my anxiety. First, the spread of nuclear weapons to unstable countries such as Pakistan and North Korea. Second, the growing body of evidence about how close the world has come, at various times, to nuclear conflict. My third reason for worry is more immediate: a significant increase in threatening nuclear talk from Russia.