Contact: Daryl Kimball, Executive Director, (202) 463-8270 x10, Gabriela Iveliz Rosa Hernández, Research Associate, (202) 463-8270 ext. 104
Cluster munitions, also called cluster bombs or CBUs, are gravity bombs, artillery shells, and rockets that fragment into small bomblets or grenades. According to the Convention on Cluster Munitions, “Cluster munition” means a conventional munition that is designed to disperse or release explosive submunitions each weighing less than 20 kilograms, and includes those explosive submunitions.
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Some cluster munitions disperse only two bomblets while others can spread up to hundreds of submunitions over a large area. These weapons are designed for use against massed formations of troops and armor or broad targets, such as airfields. Cluster submunitions, however, sometimes fail to explode on impact and can kill or maim civilians who later come into contact with them. These unexploded submunitions may remain dangerous for decades. According to Cluster Munition Monitor 2022, at least 23,082 cluster munition casualties have been confirmed globally. About 18,426 casualties resulted from unexploded submunitions and about 4,656 from cluster munition attacks. Estimated totals, however, are considered much higher, and according to the Monitor, “are likely a better indicator of the true numbers.” Estimates for the total global number of casualties range from 56,500 to 100,000. Almost all reported cluster munition casualties have been civilians, in large part because of the unwillingness of militaries to provide information.
At least 23 governments have used cluster munitions during armed conflict in 41 countries and five territories since the end of World War II. Almost every part of the world has experienced cluster munition use at some point over the past 75 years, including Southeast Asia, Southeast Europe, the Caucasus, the Middle East and North Africa, Sub-Saharan Africa, and Latin America. Although cluster munitions first saw use in World War II and more than 50 countries have since acquired stockpiles of such arms, efforts to regulate or ban the use of cluster munitions gained greater attention and momentum after the summer 2006 war between Israel and Hezbollah, a Shiite organization that the United States identifies as a terrorist group. Israel’s extensive cluster munitions use in the last 72 hours of that conflict resulted in an estimated one million unexploded bomblets scattered across southern Lebanon, arousing some strong condemnation. Jan Egeland, then-UN Under-Secretary-General for Humanitarian Affairs, blasted Israel’s use of cluster munitions as “shocking and completely immoral.”
Convention on Cluster Munitions
The Convention on Certain Conventional Munitions (CCW) did not restrict the use of cluster munitions. Although a group of states initially sought to establish a new protocol banning cluster munitions in the CCW, years of negotiations in the consensus-based forum failed to produce such a protocol. Frustrated with the slow-moving CCW approach, Norway at the November 2006 review conference announced an alternative effort to negotiate a treaty on cluster munitions. The inaugural meeting of that effort convened in February 2007 in Oslo. Of the 49 governments attending the conference, 46 ultimately signed the “Oslo Declaration” to “conclude, by 2008, a legally binding instrument that will…prohibit the use, production, transfer, and stockpiling of cluster munitions that cause unacceptable harm to civilians.”
Much of the debate among participating governments over the treaty centered on two issues. The first was whether future use restrictions would take effect immediately or, as Germany argued, be phased in to allow time for the development of alternative weapons. The second was whether the treaty should outlaw all cluster munitions or permit some exemptions for certain types or for their use in certain circumstances. Sweden called for a treaty balancing “legitimate humanitarian and military interests,” while the United Kingdom sought exemptions for systems equipped with self-destruct or self-deactivation devices that are supposed to render unexploded munitions harmless after a short period of time. Other countries, such as Norway, Ireland, and Mexico, favored a total ban.
On May 30, 2008 the Dublin Diplomatic Conference on Cluster Munitions adopted a comprehensive new treaty banning cluster munitions. 107 states adopted the treaty. The Convention on Cluster Munitions (CCM) is a legally binding international treaty that prohibits the use, production, stockpiling and transfer of cluster munitions and requires clearance of remnants and destruction of stocks. It requires states to provide assistance to survivors and their communities and builds on existing international human rights and humanitarian law. The treaty requires states to destroy existing stockpiles within eight years and to clear contaminated land within 10 years. The obligations relating to victim assistance were groundbreaking; they demanded the full realization of the rights of people affected by cluster munitions and required states to implement effective victim assistance measures.
The Convention on Cluster Munitions was signed by 94 countries at the Oslo Signing Conference in December 2008, and entered into force on August 1, 2010, after 30 states ratified it by Feb. 16, 2010. In November 2010, the First Meeting of States Parties to the Convention on Cluster Munitions (1MSP) took place in Vientiane, Lao PDR. After holding their First Meeting of States Parties in Lao PDR in November 2010, States Parties convened in Lebanon, another highly contaminated country, for the convention’s Second Meeting of States Parties (2MSP) on Sept.12–16, 2011. At the meeting, States Parties adopted the Beirut Progress Report, charting the implementation of the Vientiane Action Plan, which guides the work of the convention through to its First Review Conference in 2015. To date, there have been ten annual Meetings of States Parties, with the most recent held in September 2022 in Geneva, Switzerland.
The convention stipulates Review Conferences are to occur every five years. The First Review Conference was held between Sept. 7-11, 2015 in Dubrovnik, Croatia, and the Second Review Conference was held in two parts in Geneva, Switzerland between Nov. 25-27, 2020 in a virtual format and Sept. 20-21, 2021 in hybrid format.
Status of the 2008 Convention on Cluster Munitions
A total of 110 states-parties have ratified or acceded to the Convention on Cluster Munitions to become full states-parties, and 13 states that have signed have yet to ratify. States-parties include former producers and users of cluster munitions such as France, Germany, the Netherlands, and the United Kingdom (UK). Since the convention entered into force on August 1, 2010, becoming binding international law, states can no longer sign, but must instead accede.
A total of 53 signatories have ratified the convention since August 2010, including countries where cluster munitions have been used (Afghanistan and Mauritania), former cluster munition producers (Italy, Sweden, and Switzerland), and countries that have stockpiled cluster munitions (Afghanistan, Côte d’Ivoire, Czech Republic, Honduras, Hungary, Italy, Mauritania, Sweden, and Switzerland).
Since the convention entered into force, cluster munitions have been used in eight non-signatory states, including Azerbaijan in 2020; Cambodia in 2011; Libya in 2011, 2015, and 2019; South Sudan in 2014; Sudan in 2012–2015; Syria in 2012–2021; Ukraine in 2014–2015- and 2022; and Yemen in 2015–2017.
Russia has used cluster munitions extensively in Ukraine since its invasion on Feb. 24, 2022, and Ukraine has used cluster munitions at least three times during the war. It is estimated that as a result of cluster munitions, hundreds of civilians have died in Ukraine, and infrastructure including schools, hospitals, and homes has been destroyed. Russia and Ukraine have not joined the convention. (See ACT, October 2022).
Unilateral restrictions on use
Several states that have not joined the Convention on Cluster Munitions have imposed restrictions on the possible future use of cluster munitions. Romania has said it restricts the use of cluster munitions to use exclusively on its own territory. Poland has said it would use cluster munitions for defensive purposes only and does not intend to use them outside its own territory. Estonia and Finland have made similar declarations. During the CCW negotiations on cluster munitions, several states that have not signed or ratified the Convention on Cluster Munitions publicly stated that they were prepared to accept a ban on the use of cluster munitions produced before 1980 as part of the proposed CCW protocol, including Russia, China, India, and South Korea. The CMC urges that as an interim measure toward joining the Convention on Cluster Munitions, these states should institute the commitment made at CCW as national policy.
U.S. Cluster Munitions Policy
In June 2008, the U.S. Department of Defense released a directive requiring that any U.S. use of cluster munitions before 2018 that results in one percent or higher unexploded ordnance (UXO) rate—which includes all but a tiny fraction of the US arsenal—must be approved by a “Combatant Commander,” a very high-ranking military official and that after 2018, the United States would no longer use cluster munitions that result in more than one percent UXO.
However, in a Defense Department memorandum circulated on Nov. 30, 2017, the Trump administration eliminated the 2019 deadline to stop using cluster munitions resulting in more than one percent UXO but retained the requirement for Combatant Commander authorization for their use.
The United States is a producer and exporter of cluster bombs. In 2001, the United States adopted a policy that all cluster munitions produced domestically after late 2004 must have submunitions with failure rates of less than one percent. As with all U.S. arms exports, transfers of cluster munitions are governed by conditions restricting their re-transfer and use by importers.
One such agreement applies to U.S. cluster munitions shipped to Israel. Although secret, the agreement is generally understood to prohibit the use of cluster munitions in populated areas and against targets that are not clearly military. Following the 2006 conflict in Lebanon, the Department of State’s Office of Defense Trade Controls opened an investigation into whether Israel had violated the agreement. State Department spokesperson Sean McCormack said that the preliminary report, delivered to the president and Congress in January 2007, found that “there likely could have been some violations.” The United States sanctioned Israel for misusing cluster munitions in the past. The Ronald Reagan administration suspended cluster munitions sales to Israel between 1982 and 1988 following Israel’s widespread use of such arms during an earlier invasion of Lebanon.
While as recently as 2006, the United States opposed negotiating a protocol on cluster munitions at CCW review conferences, in 2007, it changed its position. Ronald Bettauer, head of the U.S. delegation, attributed the reversal “to the importance of this issue, concerns raised by other countries, and our own concerns about the humanitarian implications of these weapons.” Department of State Legal Adviser Harold Koh stated on Nov. 9, 2009, that the United States has determined that its “national security interests cannot be fully ensured consistent with the terms” of the CCM but that “the United States remains committed to negotiating a legally binding Protocol on Cluster Munitions in the CCW.”
The U.S. has never been a party to the Convention on Cluster Munitions and “maintains that cluster munitions have military utility, but has not used them since 2003 in Iraq, with the exception of a single attack in Yemen in 2009.” In 2017, the Department of Defense released a policy memorandum indicating the U.S., “will maintain sufficient inventories and a robust stockpile surveillance program to ensure operational quality and reliability of cluster munitions.”
Under President Joe Biden, U.S. transfers of cluster bombs are typically permissible if the bomblets dispersed by the weapons explode at least 99 percent of the time and purchasers consent to only use munitions in combat zones. The United States considers use of the munitions unlawful when “directed against civilians.”
Spurred by the use of landmines and cluster munitions in the Russian war on Ukraine, Democratic members of the U.S. Congress have called for changes in U.S. policy on such weapons. Policymakers have argued that condemnations of Moscow would be stronger if Washington would join the Convention on Cluster Munitions. As of July 2023, there have been no commitments by President Biden to change cluster munition policy. (See ACT, May 2022).
On July 7, AP confirmed that the Biden administration would send thousands of cluster munitions above a 1% unexploded ordnance to Ukraine.