The decision by the United States to send cluster munitions to Ukraine, as part of a new military aid package to bolster Kyiv’s war efforts against Russia, has raked up controversy. Cluster munitions, or cluster bombs, are weapons that release multiple explosive submunitions, also called bomblets, into the air. These submunitions explode as soon as they hit the ground, killing and maiming people in the area. Many bomblets do not blow up instantly and remain dormant for years (also known as the dud rate). These inactive bomblets act as precarious landmines, posing a grave threat to the civilian population, including women and children, for a long time. According to the Human Rights Watch, which is a civil society organisation, Russia, since launching a full-scale invasion of Ukraine, has used cluster bombs against Ukraine in cities such as Kharkiv, resulting in hundreds of civilian deaths and damaging civilian objects such as homes, hospitals, and schools. Now, Ukraine using these dangerous weapons will worsen the situation.
Cluster bombs have a notorious history. They were used in the Second World War. Since then, cluster bombs have been used on multiple occasions including by the U.S. in the wars in Vietnam, Afghanistan, and Iraq. According to the Cluster Munition Monitor, anywhere between 56,000 to 86,000 people have died in cluster munition-affected countries, since the 1960s.
Enactment of convention
Along with its increasing use, the international campaign against cluster bombs led by the civil society organisations such as Human Rights Watch also gathered momentum. This resulted in an international treaty called the Convention on Cluster Munitions (CCM) being enacted in May 2008. The enactment of the CCM has been a major step in eradicating cluster bombs. However, the treaty is not universal — 112 countries have acceded to the CCM including many North Atlantic Treaty Organization (NATO) members such as Canada, Germany, France, and the United Kingdom. But important countries such as the U.S., Russia, China, Israel, and India have not signed the CCM. Ukraine is not a member.
Article 1 of the CCM bans the use, production, stockpiling, and transfer of cluster bombs. The convention further obligates countries to destroy existing stockpile of cluster munitions in their possession. Countries are also legally bound to develop a victim assistance programme to provide support and rehabilitation to the cluster bomb victims in their jurisdiction.
Customary international law
Given that there is such an international treaty, are Russia and Ukraine violating international law by using cluster bombs? Since these countries are not signatories to the CCM, it is argued that they are not bound by international law banning cluster bombs. This is not correct.
International law on armed conflicts has always drawn a distinction between combatants and civilian populations and between civilian objects and military objectives. In this regard, a fundamental customary international law (CIL) norm applicable to armed conflicts is the prohibition of indiscriminate attacks. In other words, an essential canon of international law is that the use of force must be discriminate, that is, the force should target specific military objectives and not civilians. This CIL norm is codified in Article 51(4) of Additional Protocol I to the 1949 Geneva Conventions, to which both Russia and Ukraine are parties. Given the nature of cluster bombs, their usage is a classic example of indiscriminate use of force that fails to differentiate between combatants and civilians, or between civilian objects and military objectives, and is thus illegal.
Another fundamental international humanitarian law norm relevant here is proportionality. Codified in Article 51(5) of the Additional Protocol I to the 1949 Geneva Conventions, this rule prohibits excessive use of force that causes incidental damage to the civilian population or civilian objects, when compared to military benefits anticipated. Given the fact that the use of cluster bombs is inherently indiscriminate, harming civilians, their use will amount to disproportionate use of force and is thus illegal. In sum, even if Russia and Ukraine are not signatories to the CCM, their use of cluster bombs violates international law.
But what about the U.S.? Arguably supplying cluster bombs to Ukraine outside of the CCM, that Washington has not signed, is not a violation of international law. Moreover, it is claimed that the U.S.-made cluster bombs, unlike the Russian ones, have a low dud rate, that is, the prospects of unexploded bomblets are slim. Thus, questionably, they meet the requirements of the use of force being proportional and discriminate. Nonetheless, supplying cluster bombs to any country is an irresponsible act. The usage and the possession and transfer or supply of cluster bombs should be banned universally, as envisaged in the CCM. For this to happen, all United Nations member-countries should accede to the CCM and eradicate cluster bombs from the face of the earth.
Prabhash Ranjan teaches at the Faculty of Legal Studies, South Asian University. The views expressed are personal