Ukraine and the spread of nuclear weapons

The Ukraine conflict may well be a turning point in the spread of nuclear weapons. This is not a reflection on Ukraine itself but the lesson some governments will take from NATO's reluctance to have a head-on clash with Russia.

The lesson is clear: if you want to avoid being attacked by the US and its allies, have nuclear weapons.

North Korea has learned that lesson: it developed nuclear weapons, and so the US will now not attack it.

By contrast, Libya surrendered its nuclear ambitions to improve its relations with the west. It stopped its programme in 2003 and in 2004 British prime minister Tony Blair became the most senior British politician to visit Libya since Winston Churchill in World War II. But in 2011 the US helped overthrow the Libyan government and there has been chaos in the country ever since.

We are on the brink of unravelling decades of work in stopping the spread ("proliferation") of nuclear weapons.

A nuclear arms control breakthrough came in 1968, with the adoption of the Nuclear Non-Proliferation Treaty (NPT). It entered into force in 1970 and I attended the first NPT Review Conference in Geneva in 1975.

191 countries are now bound by it. It is one of the most widely implemented arms control treaties. Only Israel, India, Pakistan and South Sudan are not part of it.

NPT Countries with nuclear weapons agree not to supply them to countries which don't have them – and they agree to work towards general and complete disarmament.

NPT Countries which don't have nuclear weapons agree not to acquire them. They are guaranteed access to nuclear facilities if they wish to develop civilian nuclear energy (but few have exercised that right).

In the late 1960s, when I first started giving talks on the dangers of nuclear weapons, there was speculation that by the year 2000 – which seemed a long way off then! – there was speculation that 30 or more countries could acquire nuclear weapons. These included Australia, Canada and Sweden. All had nuclear programmes of some sort at that time.

Instead, the NPT created a set of mutual guarantees for peace. For example, Australia decided eventually to join the NPT and so forego its nuclear weapons ambitions. This meant that Indonesia need not acquire nuclear weapons. In turn Malaysia could also agree not to acquire any. This was a domino effect for peace.

There isn't much good news when it comes to nuclear weapons. But the NPT offered a glimpse of a better world.