Human Rights Watch is reporting today that eleven children were killed over the weekend when a Syrian MiG-23 dropped cluster bombs on the town of Deir al-'Assafeer. An indiscriminate attack of any kind on noncombatants violates international humanitarian law, but the focus in HRW's account of what happened is on the use of cluster munitions, and for good reasons.
Cluster bombs, first, are used primarily as antipersonnel weapons. When noncombatants die in an attack employing conventional bombs or artillery shells, a plausible claim can sometimes be made that the deaths were unintended collateral damage incidental to an attack on a legitimate target. On the other hand, when civilians--and only civilians--are killed by cluster bombs, there is a strong case to be made that a war crime has been committed.
Second, cluster munitions tend to leave behind a deadly legacy of what are sometimes rather bureaucratically referred to as explosive remnants of war (ERW). Everywhere they have been employed, unexploded submunitions--bomblets--continue to pose a threat to civilians (poor farmers more often than not) long after the conflict ends. Disposing of unexploded submunitions is very hazardous, requiring both resources and political will that post-conflict societies often find to be in short supply. According to HRW, video footage of the attack on Deir al-'Assafeer and its aftermath shows at least fifty unexploded bomblets around the site.
Human Rights Watch maintains that cluster munitions "are subject to a ban under international law due to the harm they cause to civilians," in the words of Mary Wareham, the organization's arms division advocacy director. The ban to which Wareham refers is articulated in the 2008 Convention on Cluster Munitions, which entered into force on August 1, 2010. The Convention today has 111 signatories, 77 of which have ratified the agreement. Syria is not a party to the agreement, however, which means the ban does not apply to it in the absence of a determination that the ban is part of customary international law (a claim that has not, to my knowledge, been pressed by HRW).
There is no question that the use of cluster munitions to deliberately target noncombatants is illegal. The deaths of eleven children in the bombing of Deir al-'Assafeer should be added to the long list of crimes for which the Assad regime ultimately should be held accountable. But it is not clear--in fact, it is almost certainly wrong to say--that international law makes it illegal for Syria to use cluster munitions under any conditions. While I would prefer to side with Wareham and Human Rights Watch on this issue, the fact that Syria is not a party to the Convention on Cluster Munitions is significant. It has opted out of the obligations imposed on states parties by the Convention, as has the United States. The right to do so, however unfortunate in this particular case, is inherent in the notion of sovereignty. Sovereignty shields states--including bad ones like Syria--from the imposition of law, including laws banning cluster munitions, by outsiders. But only up to a point.
Wareham states that "all governments, including Syria’s allies, should condemn Syria’s continued use of cluster bombs," and there is good reason for this, even if Syria is not legally subject to the ban imposed by the Convention on Cluster Munitions. The condemnation of other governments can erode the protection that sovereignty provides for the use of cluster munitions by states that have not ratified the Convention. While sovereignty ensures that states bear primary responsibility for their own laws and their own actions (at least insofar as their actions are confined to their own territories), international law as a means of limiting the freedom of states pushes back against sovereignty where customary international law and, more importantly, peremptory norms (jus cogens) are involved. If cluster munitions are to be "subject to a ban under international law," it will come from universal ratification of the Convention on Cluster Munitions or, more likely, from a sufficiently widespread acceptance of the Convention and broad-based condemnation of holdouts that, in combination, generates a customary international law norm against possession or use of the weapons. Human Rights Watch may have jumped the gun in suggesting that a ban on cluster munitions currently exists, but it is hastening the day when that will be true by publicizing what the Syrian government is doing with these weapons.