Cluster Munitions: Policy Reversal and International Law Norms

Posted in: International Law

The Defense Department recently announced a new policy on cluster munitions, reversing strong limits implemented during the Bush administration and maintained through the Obama administration and allowing changes to existing military practices. What are these changes and why do they matter? The short answer is that they: roll back an anti-cluster munitions policy position and they reflect an ongoing hostility to emerging pro-civilian international practices and a strong willingness to depart from international norms viewed as inconsistent with an America-first approach. The longer answer with explanation is below.


Cluster munitions are “bombs, rockets, and artillery shells that disperse explosive sub-munitions over wide areas.” Like all weapons in the US arsenal, the Geneva Conventions and basic international humanitarian law principles of discrimination and proportionality govern their use during armed conflicts. This means cluster munitions may not be used to target civilians unless those civilians are directly participating in hostilities, and the collateral damage to civilians cannot exceed the cluster munitions’ expected concrete and direct military utility. The Convention on Conventional Weapons Protocol V (on Explosive Remnants of War) also regulates US use of cluster munitions, as it is a state party to this international treaty. The Convention on Cluster Munitions, which over 100 countries have ratified, goes substantially further in requiring state parties to ban their use, transfer, sale, and production, as well as destroy their existing stockpiles. The United States, however, chose not to join this convention, instead pursuing additional limitations under the Convention on Conventional Weapons; adopting the domestic policy position discussed below; and largely acting in voluntary compliance with the cluster ban treaty provisions.

In addition to international law, US weapon use is also governed by domestic laws and rules of engagement. Under those rules, the US once used cluster munitions in large numbers, such as during the Vietnam war as well as in the early stages of conflict of Afghanistan and Iraq. In the wake of the 1997 landmine ban, both states and civil society began focusing on the civilian harms of cluster munitions, which when they fail to detonate, function in a manner similar to landmines. By 2005, the United States Department of Defense prohibited purchase of cluster munitions with a failure rate greater than 1 percent and more importantly, in 2008, adopted a new policy, pledging not to “use, sell, or transfer cluster munitions with a failure rate greater than one percent.” Given this policy and operational concerns, the United States has only once confirmed its use of cluster munitions after the adoption of 2008 policy.

Does it make sense for militaries to use cluster munitions? Even though the United States very rarely used cluster munitions under the 2008 policy, the government has continuously maintained that cluster munitions have military utility, especially in traditional warfare involving an invasion where they “would be very effective in terms of stopping the rapid advance of an army onto your territory or against your position.” The United States has also defended cluster munitions on the rationale that their use could create less collateral damage than the alternative of unitary weapons and argued they might be particularly useful in dealing with adversaries who use civilian shields. In contrast, opponents have criticized cluster munitions for their high dud rate, which poses an ongoing threat to civilians who live in or near the areas where they are dropped. For instance, thousands of Laotian civilians died after the end of the Vietnam war as a result of encountering unexploded cluster munitions in their everyday lives. While technology may have improved, Human Rights Watch suggests that the dud rates of cluster munitions used in recent conflicts were as high as 16% and that over 4,000 civilians were killed or injured by unexploded cluster munitions left after the Gulf War.

What Changes Under the New Policy?

Probably the biggest change under the new policy relates to cluster munition use. Combatant commanders now possess discretion to use cluster munitions that do not satisfy the procurement standards described below as well as to allow transfers of non-compliant cluster munitions to meet “immediate warfighting needs.” In other words, individual commanders could choose to use cluster munitions with a dud rate significantly higher than one percent. Relatedly, the policy eliminates the part of the 2008 Bush policy that would have banned all cluster munitions use by 2019 unless the government had acquired munitions that had a one percent dud rate or lower.

Procurement rules are also significantly altered. The DoD will be permitted to purchase cluster munitions that have more than a one percent dud rate across the range of intended operational environments so long as they either : (a) possess a non-mechanical detonation function; or (b) possess a self-destruct mechanism or (c) are automatically rendered inoperable 15 minutes after being armed. These requirements are designed to reduce the potential impact on civilians, but worrisomely, the policy provides no specifications for required failure rates of non-mechanical detonators or self-destruct mechanisms or automatic inoperability mechanisms.

What Remains Under the New Policy?

Even with such significant changes, much remains the same. Landmine submunitions are still prohibited as are cluster munitions transfers to other countries that do not satisfy the 2008 one percent dud rate policy limits. The United States still accepts the applicability of rules governing proportionality under the Geneva Conventions which should limit the operational environments in which submunitions could be deployed. For example, if the United States wanted to scatter them in a setting in which civilians are present, it would still have to conduct a proportionality analysis under international law and would likely conduct an even stricter analysis under existing policy weapon selection and weaponeering policy. Similarly, the Convention on Conventional Weapons Protocol V remains good law and requires state parties to clear, remove, or destroy any dud cluster munitions in territory they control after the cessation of active hostilities. State parties must also take all feasible precautions to protect civilians in territory under their control including “warnings, risk education to the civilian population, marking, fencing and monitoring of territory affected by explosive remnants of war.”. One should emphasize, however, that such provisions only apply to territory under the state party’s control, which does not describe many of the US military’s operational environments.

Why Does it Matter?

(a)  Possible changes on the ground

While the policy certainly allows for cluster munition use under new circumstances and conditions, it is hard to know whether the military intends to use them in ongoing conflicts or if this is more about signaling to or preserving the option of their use in North Korea. Much of this depends on whether commanders believe they have utility in highly dynamic environments like those in Iraq and Yemen. It also depends on how broadly commanders interpret the “immediate warfighting needs” exceptions and how they conduct proportionality analyses. Of course, the door is much more open than before, but the choice to actually use them may also be significantly limited by interoperability concerns. The Convention to Ban Cluster Munitions obliges state parties “never under any circumstances to…assist, encourage or induce anyone to engage in any activity prohibited” under the treaty. Article 21 makes clear this does not ban all military cooperation and operations with non-state parties that use cluster munitions, but many (though certainly not all) state parties believe they cannot carry out operations or provide other logistical assistance when cluster munitions will be used.

(b)  Rejection of emerging strong pro-civilian perspectives

Thinkng more broadly, the new cluster munitions policy also strongly rejects the international trend toward increasing civilian protections. Take the widely ratified landmine ban, for instance. While the United States did not ratify the global landmine ban during the Clinton, Bush, and Obama administrations, it maintained a domestic policy significantly limiting the use of landmines and consistently moved in the direction of treaty compliance. Civil society campaigns continue to press for ever greater per se bans on weapons to protect civilians such as the Nobel prize–winning International Campaign to Abolish Nuclear Weapons and the Campaign to Ban Killer Robots. While the United States showed no sign of joining these campaigns, nor ratifying the cluster munitions ban under prior administrations, this cluster munitions policy reversal is a much more public step away from the trend. It is also accompanied by concerns that the Trump administration is much less protective of civilians on the ground than the Bush and Obama administrations were. For instance, the number of civilian casualties in strikes against ISIS is notably and regrettably on the rise. While such increases might reflect changing strategy and the nature of the specific conflicts, they might also reflect the Trump administration’s “relaxed oversight, investigation and accountability on civilian casualties.” One might view this new policy, then as part of this larger move away from acting to limit civilian casualties as much as possible.

(c) Departure from international norms and practices in favor of “America First”

Viewing this change in policy position on cluster munitions from an even greater vantage point, one might discern a larger pattern of the Trump administration’s exit from existing and emerging international practices it considers at odds with an America-first approach. This is a significant departure also from the prior administration’s internationalist stance. I suggest this new policy might be viewed as part and parcel with the high-profile withdrawal from the Paris climate agreement, the partisan withdrawal from UNESCO, and most recently, the withdrawal from United Nations migrant and refugee pact. None of these changes violates international law per se or even necessarily demonstrates disrespect for international law generally, but together they do suggest a deep disagreement with the underlying substantive positions and an unwillingness to maintain a status quo where the United States, despite failing to join certain international law treaties remained largely committed to compliance with their underlying norms via domestic policy positions and non-binding international law efforts. Instead, they might be collectively viewed as the early implementation of the emerging America-first doctrine.

  • Frank Willa

    Professor, thank you for highlighting this topic. My view is that this “America first doctrine” does mark a significant departure from of both international and national norms. This has been the practice of Trump and his conservative supporters for quite sometime. They have ignored and disparaged current norms, the list of examples has been too long to catalogue here. Fortunately, many of the commentators for Verdict have written about this as it happened before the campaign and during this first year of this administration; as well as citing the corrosive harm it would cause. The “conservative movement” is very reactionary- that is it reacts from the present and harkens to fantasized notions of an alleged time gone by when things were supposed to have been better. It rejects current reality, and somehow thinks that the values or norms that have been rejected as part of the march of humanity toward a better world should be resumed. They seek to impose their views on the rest of the world, thinking somehow that if they do so, everyone will come to agree with their thinking. My take on this conservative movement is that the adherents miss the “beauty” of the country created by our constitution. It provides for the improvement of the general welfare- that is progress rather than cultural stagnation. And it assures the diversity of thought and its free expression; understanding the corrosive society that is formed when strict compliance to a single set of beliefs is seen as the way to run a country. Mankind has progressed in spite of those that would – in my view- cling to the past out of fear of change. Here the world has adopted the norm that rejects wanton and indiscriminate destruction by weaponry created as our science and technology has moved forward; we banned gas warfare and constrained these cluster bombs. This step backward that you have noted, should be a cause for alarm; and, yes it is sadly but a part of the larger agenda.