It’s clearly a historic moment, but hardly a very encouraging one. For today – Feb 5 – marks the expiry of the last treaty between Russia and the United States designed to limit the number of strategic nuclear forces each side can deploy against the other.

Russia and the US – which between them account for around 90 per cent of all nuclear warheads – now no longer face any restrictions on how many such weapons they produce or deploy. More than that, the end of the so-called New Strategic Arms Reduction Treaty – or New START – will spur a global nuclear arms race, with all the risks of a catastrophic miscalculation.