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Cluster bombs are horrible munitions that can cause extreme injury or death—just like many other munitions.

Given the controversial nature of these munitions, can a case be built to justify the US giving Ukraine cluster bombs to aid their defense against the Russian invasion?

As is often the case, this is a moral dilemma without a glaringly obvious solution. Instead, there are several options, all of them bad. The idea is to choose the option that is less bad.

Some context

Before we get into the long weeds of morality and evaluating the US actions, it is worth pointing out a number of facts.

First, Russia has already been using cluster munitions. Indeed, last year in an act of heinous revenge for the Ukrainians having the gall to successfully defend themselves, the Russian forces bombarded the city of Kharkiv repeatedly with all sorts of munitions, including cluster bombs. And they were targeting civilians.

Second, Ukraine already has NATO-country-donated cluster bombs. Turkey has been giving Ukraine cluster munitions for some time, so the recent move by the Biden administration isn’t crossing any red line. That line was crossed last year and was already trampled by the Russians.

Though neither of these points alone justifies the Ukrainian use or American donation of these shells, it is useful context.

What are they?

The cluster munitions in question are called DPICMs, or dual-purpose improved conventional munitions. The specific cluster munitions Ukraine will receive are the M864 & M483A1 155mm artillery shells. These are designed to carry either 88 or 72 grenade-like submunitions. They are designed to burst at an optimal height above a target and scatter the submunitions to cover a much larger area than otherwise would have been affected.

The issue with these munitions is that some of the submunitions fail to detonate, being left where they fall to potentially be found and triggered later. The shells that the Russians used in Kharkiv, for example, have an estimated “dud rate” of around 30%, while the aforementioned American munitions have a dud rate around 2.35% (albeit in more perfect test conditions—the real rate will be higher).

Cluster munitions like these have been used over the 20th and 21st centuries and have led to civilian deaths and casualties long after wars have receded from conflict zones. Such risks to civilians in peacetime have led many people to castigate the use of such munitions.

The Convention on Cluster Munitions was adopted in 2008 by a number of countries, with at present 111 nations having ratified it. The treaty prohibits all use, transfer, production, and stockpiling of cluster munitions.

Neither the US, nor Russia, nor Ukraine are signatories to the treaty. And when some people claim this is “prevailing international law” or similar, it is worth noting that only two of the 10 most populous countries in the world are signatories to the convention (Nigeria and Mexico).

So it might well be that most people on Earth are not subject to this convention.

Understanding the war

Not only have Ukraine asked for these munitions, but they actually desperately need them. The Ukrainians are in the midst of a counteroffensive that is make-or-break for succeeding in the defense of their homeland. If the war drags on too long, or if the counteroffensive is not successful, then Western aid and interest might well dry up. Elections can change political landscapes, and Ukraine knows they are not guaranteed continued support (which is why the recent NATO summit was so incredibly important to them).

The success of the counteroffensive is intrinsically linked to the stocks of ammunition, particularly artillery ammunition, that Ukraine has. This is by and large a war of artillery. At its peak, Russia was firing 60,000 artillery shells per day. Ukraine has been unable to get near that figure. However, Russia’s firing rates have diminished as their own stocks have started to run dry, whilst their production isn’t remotely in a place to produce those levels. # Moreover, Ukraine has been explicitly targeting Russian artillery pieces and ammunition stockpiles for months, helped by US-provided HIMARS, European equivalents, and UK-provided Storm Shadow cruise missiles.

But without shells of their own, Ukraine’s counteroffensive will come to an abrupt halt. Successful wars, in NATO doctrine, are combined arms initiatives, meaning they require all aspects of the armed forces to commit to such maneuvers, from infantry to artillery, tanks and other mechanized equipment to drones and logistics.

And aircraft. Mainly, initially, a lot of aircraft.

Ukraine has a small air force that, amazingly, still functions. But the older craft they use do not have the range on their weapons to support their troops. It is too dangerous. Although the Russians do not have air superiority or supremacy (the airspace is still contested), they have the advantage of longer-range radars and missiles.

Ukraine’s overwhelming need for them

Where Ukraine cannot use close air support to enable operational success, they have to pick up the slack elsewhere—with artillery. The Russians have had months to dig in and have successfully built up to four lines of trenches in many areas, laid with fields upon fields of mines. Whether anyone likes it or not, the exact areas where Ukraine will be using cluster munitions are already absolutely laden with anti-tank and antipersonnel mines.

In the second part of the mine roller footage below, after detonating an anti-tank mine, I count a further six mines being detonated in about six meters:

Existing Russian doctrine would have about 1000-1500 mines per square km. The landscape is littered with Russian mines and minefields.

In other words, cluster munitions would be fired in areas that would already require extensive demining after the war is over.

The acute need for these weapons is twofold. First, these DPICMs are the ideal munition for dealing with the extensive trench networks that the Russians have built up. They may even help with clearing minefields from a distance ahead of Ukrainian maneuvers (the Ukrainians have already lost a number of demining vehicles as these are often sent in first in very vulnerable situations).

But, most importantly, they just need shells. Artillery is that important and the shell hunger is that bad. The US government facilities and at least six private defense concerns have ramped up shell production to levels not seen since the Korean War. Europe, Australia and other nations around the world are also helping out. But, right now, the need for these shells is huge. And the US, in decommissioning these shells for a new type of weapon to replace them (AWP—Alternative Warhead Program), has literally millions of these to spare. The US would have to pay for these to be properly dismantled. Or, they could give them to Ukraine, which desperately needs them.

In the absence of a worldwide supply of artillery shells, there are millions that will otherwise be destroyed. And I cannot overemphasize how desperate the Ukrainians are and have been for artillery ammunition.

“It was a very difficult decision on my part. And by the way, I discussed this with our allies, I discussed this with our friends up on the Hill,” Joe Biden said in justifying his decision. “The Ukrainians are running out of ammunition.”

He continued, saying, “This is a war relating to munitions. And they’re running out of that ammunition, and we’re low on it. And so, what I finally did, I took the recommendation of the Defense Department to—not permanently—but to allow for this transition period, while we get more 155 weapons, these shells, for the Ukrainians.”

The idea is that until global conventional artillery shell production can ramp up enough, DPICMs will provide the much-needed stop-gap.

It is also important to emphasize the relative effectiveness of these munitions:

Jack Watling and Justin Bronk, both senior research fellows at the Royal United Services Institute in London, recently wrote that cluster munitions would “greatly multiply the efficiency of artillery fire against entrenched troops.”

They pointed to U.S. army data that found that during the Vietnam War, the number of conventional high-explosive 155-mm rounds fired for each enemy soldier killed in combat was 13.6, compared with only 1.7 for cluster munition shells.

“When fired against Russian defensive fortifications in Ukraine, a conventional artillery shell has a very low probability of killing Russian troops unless it lands directly in a trench,” they wrote.

“Much of the world says they’re immoral. So why is Ukraine so keen on cluster bombs?”, CBC

Because Ukraine would need far fewer rounds to exact the same damage, they would use far fewer artillery shells in total to succeed in their counteroffensive. The use would allow Ukraine “to sustain the fight for significantly longer,” Watling and Bronk wrote in their piece “Giving Ukraine Cluster Munitions is Necessary, Legal and Morally Justified” for the Royal United Services Institute.

There are further knock-on effects: The life of a howitzer barrel is finite, and the wear and tear on them is a huge consideration. The authors note that, “With each barrel having a life of around 1,800 rounds, giving Ukraine DPICMs will mean it has to fire fewer total rounds for a given battlefield effect, allowing it to sustain the fight for significantly longer.” Thus the stocks of artillery pieces and barrels are affected, too.

The philosophy

This is, of course, a manifestation of the well-known trolley problem, a case of the ends justifying the means. In classic moral consequentialist morality, should one pull the lever to change the route of a trolley hurtling toward killing five workers on the train track, so that it careens into a single worker instead? One death is preferable to five, so the calculation goes.

Moral consequentialism: The moral quality of an action is completely determined by the consequences of the action, though there are is a host of different ways that this evaluation can be calculated.

The President understands the risk: “But the main thing is they either have the weapons to stop the Russians now—keep them from stopping the Ukrainian offensive through these areas – or they don’t. And I think they needed them.” Ukraine (and here with the US) either pulls the lever or it doesn’t.

Lest we now forget, it was this thinking that underwrote the firebombing of Tokyo and the dropping of atom bombs on Nagasaki and Hiroshima. Three cities full of civilians were directly targeted, killing some 300,000 civilians in the hope that the war with the Japanese would be shortened. It is like that whole set of events is so embedded into our cultural memories that it bypasses our moral evaluation.

In the case of cluster bombs, the situation is far, far more benign than hammering civilians directly with atom bombs.

Ukraine’s Defense Minister Oleksiy Reznikov explained how Ukraine will use US cluster munitions:

  • The munitions will not be used on the territory of the Russian Federation but only for the de-occupation of internationally recognized Ukrainian territories.
  • The ammunition will be used only in places where the Russian military gathers.
  • Ukraine will keep strict records of the use of these weapons and the local areas where they will be used. After liberation, these areas will be prioritized for demining.
  • Ukraine will report to partners on the use of these ammunitions and their effectiveness.

Here we have the Ukrainians setting out an agreement that civilians will not be targeted and that there will be a general understanding of where these munitions will be in order that they can subsequently be cleared up. This would then avoid the sorts of civilian deaths that have been seen in Cambodia or Iraq. The munitions will be used by the Ukrainians primarily against Russian trenches in fields and treelines, away from civilian centers.

Cluster bombs constitute a far more benign situation than hammering civilians directly with atom bombs.

The principle of using cluster munitions is the same as that of atom bomb usage: The sooner this war is brought to an end, the fewer lives will be lost. As the aforementioned Watling and Bronk wrote about cluster munitions usage, “This is vital given Russia’s current strategy of attempting to dig in and prolong the conflict… Since Russia’s current strategy relies on outlasting Western military support capacity, improving the sustainability of Ukraine’s artillery capabilities would also increase the incentive for Russia to end the conflict. ” Cluster munitions would, therefore, shorten the overall length of the conflict.

Also, if Ukraine can prevail, then the right side wins, in simplistic terms, and these munitions would help to that end. But there are significant differences in terms of civilians affected compared to 1945 Japan, and even the use of cluster munitions in previous wars. Ukraine understands the use of these munitions and the future potential problems that may well be entailed. Yet, I wager, if you were to ask Ukrainians themselves whether they should be provided, I imagine there would be overwhelming support.

Even if there is a problematic dud rate, and even if some civilians might die after the war finishes, as sad as that may be, it is a price worth paying given the huge benefits these munitions would provide.

There is another issue with the approach of some critics to the use of cluster munitions. That is that cluster munitions are somehow different, perhaps a different category of weapon because of their failure to explode. But many weapons do this. It is estimated that one in five of Russia’s munitions stocks are unsafe due to their condition and age. As mentioned, Russia has fired their weapons indiscriminately any civilians for well over a year, and it seems somewhat disingenuous when certain people get particularly irate now, and yet have previously remained silent.

As Watling and Bronk conclude:

In summary, therefore, the objections to DPICM provision to Ukraine are militarily dangerous, legally misleading and morally questionable, drawing a false equivalence between Russian and Ukrainian use cases. The use of such weapons by the AFU on their own territory, at their own discretion, against fortifications in open countryside, and against hostile forces who routinely fire Soviet-era cluster munitions and other highly unreliable HE munitions into civilian cities would, therefore, be consistent with the principles of proportionality and discrimination.

War is terrible. Munitions of every type and size have horrific outcomes. The hope in Ukraine using these munitions that they have asked for is that they can defend their homeland, and the freedom of others, in the most effective way possible, leading to this war coming to the best conclusion it can in the quickest timeframe.

As such, (and this is not something I would have predicted myself saying a decade ago) I not only find the donation of these munitions to Ukraine morally permissible, but a moral imperative.

A TIPPLING PHILOSOPHER Jonathan MS Pearce is a philosopher, author, columnist, and public speaker with an interest in writing about almost anything, from skepticism to science, politics, and morality,...

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