Peter Beaumont says of chemical weapons that “the idea that other weapons are equally deadly misses the point, which is that we have decided that this class of killing – like the wanton murder of civilians and shooting prisoners – is beyond the pale” (Poison gas has been taboo for a century. It must remain so, 19 April). However, he misses a wider context himself – that the world order is one in which stronger nations use their military and economic power to subdue weaker ones with impunity. As long as this is the case, less strong countries will use whatever means come to hand to try to level the playing field; much like a resistance movement does to a foreign occupier. We don’t, for instance, condemn the Maquis their second world war excesses in murdering captured German soldiers.

The obvious answer to stopping the use of chemical weapons is to strengthen global multilateral bodies like the UN, and give them greater powers to regulate and conciliate international disputes. Donald Trump wants to degrade the UN and starve it of funds. The US will no doubt have much greater “success” in its anti-UN endeavour than its token strikes against supposed chemical weapons facilities in Syria will have in stopping the proliferation and further use of chemical weapons.

Joe McCarthy

Dublin, Ireland

• Why are three of the world’s biggest exporters of arms so obsessed with the taboo on chemical weapons? They invoke the inhumanity of chemical weapons to justify intervention in Syria. Yet they have no compunction about other horrible materials that they continue to develop and produce, including the worst of them all, nuclear weapons.

Recent amendments to the Rome statute of the international criminal court reinforce prohibitions on various inhumane weapons when used in internal conflicts. It seems ironic that neither Britain nor France have ratified these amendments.

Could it be that among the “humanitarian” motives of Donald Trump and his myrmidons in Britain and France in enforcing the taboo on chemical weapons is a desire to prevent proliferation of the “poor man’s weapons of mass destruction” so as to better preserve the monopoly of a few states over nuclear weapons, the rich man’s weapon of mass destruction?

William Schabas

Professor of international law, Middlesex University London

• One of your correspondents (Letters, 19 April) argued that “if in 2011 we had sided with Russia and supported the legitimate and stable government of Syria”, it would have saved the immense loss of life and destruction of the country. He blames us all as “willing accessories” to this destruction. His description of the regime gives the game away: legitimate and stable. Certainly it was internationally recognised and until 2011 stable. But it was a dictatorship based on the subjection of the great majority of Syrians to a small minority. Its stability had come from “a peace of the dead” following the brutal suppression of the majority Sunnis by Hafez al-Assad at Hama in 1982.

This majority had a legitimate right to demonstrate for freedom and democracy. Sadly, the Assad regime replied with brutal repression and not surprisingly some Syrians reacted with violence. The destruction of Syria was caused by the persistent refusal of the Assad regime, backed by Russia, to negotiate a settlement and its cynical fostering of extreme jihadist groups in order to discredit the opposition.

Keith Morris

London

• Peter Beaumont writes that the use of chemical weapons has been “taboo” since the second world war, until Bashar al-Assad allegedly used them against his own people during the current Syrian conflict. How quickly the tragic story of the Kurds is forgotten. During the Iran-Iraq war, Saddam Hussein savagely gassed several Kurdish villages, using chemical weapons given to him by the United States. This war crime elicited no humanitarian intervention from the west, as at the time Hussein was a close ally of the US in his war against the Islamic Republic of Iran.

History unfortunately repeated itself earlier this year when the Kurds, former allies of the west in their fight against Islamic State, were savagely attacked by the Turkish army and a mercenary force made up of various Islamist groups. The western powers, as well as western commentators, saw no need to argue for an intervention to help the Kurds, who were once again left to suffer their fate.

Beaumont also ignores the murderous use of various chemical agents by the US military in Vietnam. Napalm and Agent Orange were both key elements of American strategy during the Vietnam war. Vietnamese people continue to suffer the deadly consequences of the use of chemical defoliants in the form of rare cancers and birth complications.

Zev Moses

Vancouver, Canada

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