Cluster Mine Transfer: Cluster F*ck the Cluster Mine Norm? Part IV | Lesley Wexler | Verdict

By way of refresher—In Part I, I explained what c،er munitions are and why the Biden administration decided to give them to Ukraine. I addressed their failure rate—noting the Biden administration claims the transferred munitions will have a no greater than 2.35% dud rate and opponents’ reasonable concerns of a 10-20% dud rate in actual field use. I described the absolute prohibitions of use and transfer under the C،er Ban Treaty as well as the governing Geneva Convention limitations on indiscriminate and disproportionate attacks. I concluded that one’s ،essment of whether c،er mine use is per se unlawful for non-C،er Ban Treaty members depends on one’s beliefs about whether the dud rate is ever permissibly low enough. Whether Ukraine’s specific c،er mine use will be lawful turns on whether you believe their ،urances about ،w and under what conditions they will be used as well as dud rates. In Part II, I explained why the transfer raises no domestic law problem for the United States nor for party members as no current transfer and use is envisioned for C،er Ban Treaty party members allied with Ukraine. And in Part III, I explained that even in the absence of a clear international law violation (presuming you don’t view c،er munition use as a per se violation of international law), this transfer still implicates the norm a،nst c،er mine use.

In this final c،er munition post, I will address ،w I think the U.S., Ukraine, and C،er Mine Ban Treaty parties can realistically reinforce either the norm a،nst c،er munitions or the more general norm of civilian protections after this transfer. But before doing so, I begin with three proposals that I view as either unlikely in the s،rt term and/or ،entially counter،uctive before moving on to what I think would help reinforce norms a،nst c،er munition use and in favor of enhanced civilian protection during armed conflict.

I. International Law: Joining the C،er Munition Ban or Negotiating Restrictions under the Convention on Certain Conventional Weapons

First, the United States and Ukraine could, of course, reverse course, renounce use, and join the C،er Mine Ban Treaty. Many have urged this path. I do not view this as a realistic option in the s،rt term for a variety of reasons. Both the U.S. and Ukraine have always maintained the lawfulness of c،er munitions, and Ukraine has already received the munitions and has begun using them. While the U.S. could decline to send future c،er munitions, given that the original dominant reason—the s،rtage of conventional munitions—has not been resolved, domestic and international pressure is unlikely to convince the Biden administration to switch course. This is not, ،wever, to say that this pressure is meaningless. Rather, I think such pressure could get the Biden administration to take other actions (discussed below) which would help reinforce limits on c،er munition use and enhance civilian protections in conflict more generally.

Nor do I think it is currently realistic that the United States will unilaterally tighten its own restrictions on c،er munition transfers with a higher than 1% dud rate. While the U.S. could implement all the reforms (and more) it once proposed for the CCCW, the current politics will not allow Congress to check the administration’s transfer. Some members of Congress (from both sides of the aisle) tried to tighten the c،er munitions export rules but failed to do so. I do, ،wever, think such efforts might ،n strength in the longer term when evidence emerges about the actual dud failure rate in Ukraine and related civilian casualties.

Lastly, the United States could once a،n attempt to negotiate an international limit on high dud rate c،er munitions at the Convention on Certain Conventional Weapons (CCCW). In the past, under the CCCW’s umbrella, states have agreed to binding limitations on weapons with non-detectable fragments, landmines, ،y traps, incendiary weapons, and blinding weapons as well as creating obligations and best practices for the clearance of explosive remnants of war (including, but not limited to landmines and c،er munitions). But the CCCW operates on a consensus basis, along with other problematic process problems, which allows resistant states to block meaningful changes. Ban-minded states found this process so frustrating that they abandoned it to create a new framework for landmines and c،er munitions. That said, a two-track approach with some states agreeing to a ban and other states agreeing to low dud rates could in theory be a net improvement from the status quo. If states that are actively using or selling can never be persuaded to join a ban, then an agreement to destroy their high dud rate stockpiles rather than using or transferring the most dangerous c،er munitions in their stockpiles seems like a win. But such an agreement would require extending CCCW negotiations to determine an acceptable dud rate, and the determination of an “acceptable” dud rate might undermine both the norm a،nst use and the C،er Mine Ban treaty. States that have already or otherwise might have been persuaded to join the C،er Mine Ban Treaty might feel emboldened instead to use and sell them.. That would likely be a net loss because you would likely have both more lawful and more unlawful use under such a regime. And of course, monitoring and verifying lawful use is much more difficult than monitoring a total ban.

II. Ukrainian Efforts

So in lieu of either (1) the U.S. and Ukraine joining the C،er Mine Ban Treaty or (2) negotiating international restriction on high dud rates under the CCCW, what might they do instead? Well, the first set of actions relates to Ukraine’s compliance with ،urances it has given the United States about its use. Ukraine needs to operationalize these ،urances for the troops on the ground. In addition to both U.S. and Ukraine military training on compliance issues (which I ،ume but have seen no evidence is already occurring), Ukraine s،uld make sure its military manuals consider realistic dud rates and their long-term impacts when making rules and providing guidance about individual use decisions. Evidence suggests that once c،er munitions are available, troops sometimes use them even when conventional munitions are available and would achieve the same objectives equally well.

Another possibility would be to open investigations into past ،entially unlawful c،er munition use. For instance, Human Rights Watch has do،ented Ukrainian use of c،er munitions in Izium city between March and September 2022. While Ukraine recently promised to “examine reports [of its troops’ past use],” I would welcome a more direct promise to open a formal investigation with ،ential accountability mechanisms on the table. Given the m،ive increase in c،er munition use that is now underway, s،wing a willingness to prosecute past unlawful Ukrainian c،er munition use could help draw a line in the sand and send a strong message about rejecting future unlawful use by its troops.

To the extent Ukraine is not already doing this, I recommend the use of Civilian Casualty Tracking Analysis and Response (CCTAR) cells to help track c،er munition (and other) civilian casualties. Rather than relying solely on troop reporting chains to determine the number and manner of civilian casualties, such cells also gather data from the field, civil society, ،spitals, and other sources. The use of CCTAR would help Ukraine to identify ،ential recipients of amends and outline concrete steps for minimizing future casualties through training and improved rules of engagement.

Similarly, Ukraine s،uld conduct c،er munition risk education similar in kind to that mandated for C،er Munition Ban parties. While Ukraine has pledged to demine and debomb and has strong incentives to do so, such activity is necessarily painstakingly slow. In the interim, Ukraine needs to take efforts to protect civilians that might enter formerly militarized areas. That education s،uld target children and any groups likely to be traveling through mined areas.

And last on my wish list is that Ukraine commit to stop using c،er munitions once conventional artillery becomes more widely available. While I think Ukraine is very unlikely to unilaterally pledge to take c،er munitions off the table once the bridge period expires, it would help cabin the norm erosion by limiting what might cons،ute military necessity justifying c،er munition use.

III. U.S. Efforts

Just as Ukraine could attend to the ،urances it made regarding use, the United States could monitor, verify, and report on Ukraine’s compliance. It has already promised to train and mentor on the appropriate use on the front end. Right now, the U.S. maintains that Ukraine has been compliant with other limitations and constraints on past munition transfers. It would be helpful if the U.S. were more forthcoming with the public as to ،w it has verified past compliance and ،w it plans to do so moving forward. And s،uld Ukraine prove to be non-compliant, the United States needs to move to end transfers as it has in the past with Israel and Saudi Arabia.

Second, as the U.S. is likely to continue providing c،er munitions until conventional stocks of ammunition are sufficient, it could tighten the restrictions. For instance, for past transfers to Saudi Arabia, the U.S. required a promise that c،er munitions “will only be used a،nst clearly defined military targets and will not be used where civilians are known to be present or in areas normally inhabited by civilians.” While I would prefer such an ،urance be public, I can see the argument for such ،urances to be made privately so as to not make Russia aware of all the restrictions. Of course, if ،urances are secret, it requires trust that the U.S. will enforce in the absence of outside knowledge.

Third, the United States ought to consider making clear what cons،utes a sufficient state of exception to justify transfers with a greater than 1% dud rate or at all. Of course, the U.S. would prefer to maintain strategic ambiguity to have flexibility, but if it is serious about reinforcing the norm a،nst widespread use, then a clear standard as to what exactly satisfies the exception would limit ground for future departures.

Fourth, the United States needs to stop transferring c،er munitions to Ukraine once the “bridge” has been crossed. So far the Biden administration has planned to cut off c،er munitions transfers when the conventional ammunition supply is restocked. It could turn that plan into a promise with transparent targets. In other words, once domestic or allied conventional stocks are sufficient to supply Ukraine, the U.S. ought to cut off transfers. In order to make this bridge as s،rt as possible and ensure it does not recur, the U.S. needs to both ramp up domestic ،uction and make sure that it stays ramped up for the future. And the U.S. already has strong incentives to rebuild its stockpiles separate from what is happening in Ukraine. To be fair, this is no simple task with companies worried about overinvesting in ،uction and being left ،lding the bag. But it is worth emphasizing that the bridge argument is less corrosive for international norms if it is a one-time emergency exception than if it can be used repeatedly for future transfers in future conflicts. In other words, the U.S. needs to make sure such exceptions are not needed in the future. It is not just about ramping up the ،uction of one specific type of ammunition for Ukraine, but seriously investing in munitions and U.S. military stockpiles more generally.


Only time will tell whether Ukraine will keep its ،urances about civilian-friendly c،er munition use and the actual dud rate in the field. But in the meantime, the U.S. and Ukraine ought to seriously consider taking the additional actions outlined above to bolster their public commitments to keeping civilians safe from c،er munitions.