Modern conventions on war have banned the use of chemical weapons because of the painful and indiscriminate manner in which they inflict death on all in their way.

This is why the use of chemical weapons by the Syrian regime — according to intelligence reports from the US and France and statements by the Arab League — is a clarion call to action by the international community, even though it has killed uncounted thousands with bombs and bullets over the past two years while many just stood by.

However, the moral and legal enforcement of international laws and conventions depends on the agreement of — and joint action by — the countries of the world, which are represented at the United Nations. This is the message that is being sent to the US by the Arab League, the parliament of the United Kingdom and many other world leaders and ordinary people.

The UN is presently finalising its investigation into the use of chemical weapons in Syria, which will be the basis for the action it will take against Syria. Any international action must be authorised by the UN.

Finding himself with few allies, US President Barack Obama, whose administration has been leading the charge for military action against the Syrian government, has turned to the US Congress to approve what will be unilateral action. His administration is fiercely lobbying for their blessing.

However, a delegation from the Russian parliament is planning to meet with Congress to lobby it to take a stand against US military intervention. The initiative is not likely to have much effect on the outcome of the deliberations of Congress, but will underline to them how discredited unilateral US action is in the wake of the wars in Iraq and Afghanistan. The world is making it clear that it does not want an American policeman.

The UN is often bureaucratic and ineffective, but it is the only organisation that can mandate international military action against the Syrian government — no matter how heinous its crimes.