THE international concerns about the nuclear threat from North Korea would benefit from some historical context (“Trump ramps up nuclear rhetoric after North Korea's H-Bomb test”, The Herald, September 4). Almost 50 years ago the Nuclear Non-Proliferation Treaty came into force. The deal was that signatory countries which did not have nuclear weapons would not seek to acquire them and that the existing nuclear weapon states would, according to Article 6,"undertake to pursue negotiations in good faith on effective measures relating to the cessation of the nuclear arms race at an early date and to nuclear disarmament and on a Treaty on general and complete disarmament under strict and effective international control".

The nuclear weapon states, including the UK under both Conservative and Labour Governments, showed a total contempt for the pledge to which they had signed up. Yes, there was eventually a reduction in the number of warheads, many obsolete, but there has been a relentless drive to increase the power and accuracy of their arsenals. The UK is in the process of renewing at great cost its nuclear weapons system. Instead of seriously pursuing disarmament, especially after the collapse of the Soviet Union, and putting an effective international surveillance and control system in place, we saw the arrogant assertion of entitlement by the nuclear powers.

North Korea acceded to the Non-Proliferation Treaty in 1985 but announced its withdrawal in 2003 – an interesting date. The invasion of Afghanistan followed by Iraq had clearly sent a message to regimes like North Korea: if the US doesn't like you, your turn may be next. While it is an appalling regime with a leader who seems as unstable as Donald Trump, responsibility for where we are now rests to a great extent with the older nuclear powers who failed the rest of the world because nuclear weapons represented power and prestige.

There is a glimmer of hope. Despite all the pressure from the nuclear states, 122 countries in the world agreed on a nuclear ban treaty in July and this will be open for signature on September 20. This may be the last chance for the world to start on the long journey to a nuclear weapons-free world.

Isobel Lindsay,

9 Knocklea Place, Biggar.