The US insists it will launch a strike against Syria. Nevertheless, US President Barack Obama has said he will first seek permission for military action from the US Congress. It seems that he has toned down his original bombastic rhetoric. This can only be good news for the international community and has been welcomed by international law groups.
In terms of international law, the US has yet to provide a legal basis for military action. Even if the US Congress agrees to a limited strike, this would not in itself constitute sufficient foundation for such action in international law. The legal basis for military action against Syria is currently the subject of intense debate by international law groups and the vast majority take the position that there is as yet insufficient basis for a strike.
According to the UN Charter, the use of military force by one nation against another is absolutely prohibited, unless it is in self-defense or has been permitted by the UN Security Council. In this case, the US has not been attacked and so it cannot claim to be acting out of self-defense.
The use of chemical weapons is banned by a 1925 Geneva Protocol and the 1993 Convention on the Banning of Chemical Weapons, as well as a host of international practices and conventions. If Syria did use them it was in clear violation of international law, but this in itself does not mean the US has the right to unilaterally decide to launch a military strike against Syria.
What of the UN norm of the responsibility to protect? Can this be used as a legal basis? According to this norm, members of the international community have a responsibility to prevent a state from visiting mass atrocities on its citizens. However, while it provides that countries accept that a state cannot commit a mass atrocity against its people, there is no agreement on whether a third party country can resort to military action to prevent it. Countries subscribing to this norm still hold that only the UN Security Council can determine whether to authorize military intervention.
Can the principle of humanitarian intervention legitimize the use of military force, as a British government legal memo over the crisis maintained?
Humanitarian intervention has three basic requirements. First, there needs to be a general consensus within the international community that there is clear evidence confirming that a large-scale, extreme humanitarian crisis has taken place that requires immediate action. Second, there needs to be an objective and clear assessment that people will die unless military action is taken. Third, the use of force must be proportionate, and limited in time and scope strictly to the degree that it achieves the objective of saving those lives.
Although the British government felt confident that the situation in Syria complied with the requirements, public opinion remained unconvinced there was sufficient evidence and the British House of Commons rejected the government’s case.
Whether a country can legally resort to military force depends on the permission of the UN Security Council: It is therefore crucial to prove that the Syrian government launched the attack.
Both China and Russia have said they oppose the use of chemical weapons. If the UN inspectors or the US can provide incontrovertible evidence, and if Russia and China still insist upon using their power of veto, the US could appeal to humanitarian intervention as its basis in international law to say that there was a strong case for the legitimacy of military action. For the international community, establishing a basis in international law, however unconvincing, is better than simply flouting international law altogether.