There is a common misconception that the leaders of nuclear states have a ‘red button’ that can unleash Armageddon. As Vladimir Putin continues to hint at the use of non-strategic (‘tactical’) nuclear weapons in Ukraine, there is some comfort in the knowledge that it is not so easy.

Ironically, launching the kind of strategic nuclear missiles whose use would likely spiral into global destruction is somewhat easier than deploying the smaller weapons which – however vastly unlikely – could conceivably be used in Ukraine.