The war in Ukraine has settled into a grinding fight for yards. Ukrainian and Russian forces are shelling each other with medium- and long-range artillery, leaving the already battered villages and towns of the Donbas caught in the crossfire. Like the brutal battles of World War I, the current conflict has seen only small swaths of territory change hands, often being captured and recaptured from one week to the next. Although talk of a rapid victory for either side has largely disappeared from the headlines, analysts and officials still debate what piece of heavy military equipment or new technology might turn the tide in Ukraine’s favor. With Russia running low on supplies and manpower, for instance, retired U.S. Army General Ben Hodges told The Washington Post last week that an influx of more sophisticated Western weaponry could allow the Ukrainians to turn back Russian advances and go on the counteroffensive.

This emerging war of attrition, however, is more likely to come down to “sustainment”—the ability of each side to ensure a relentless influx of troops, ammunition, and heavy equipment to the frontlines in the east, especially as the conflict drags on and international attention dissipates. Logistics, financial management, personnel services, and health services will all be central to this effort, determining which side is better able to replace its depleted units, resupply and maintain its equipment, and source food, fuel, and ammunition. The Russian military is clearly showing signs of strain, especially when it comes to reinforcing its troops after heavy losses. But so are the Ukrainians, who in recent weeks have warned that they are running out of ammunition and losing as many as 200 soldiers per day.

In a conflict that is increasingly likely to end—or at least be contained—with a negotiated settlement or cease-fire, sustainment could provide vital leverage for Ukraine. By reinforcing its troops and resupplying and maintaining its equipment, Ukraine may not be able to beat the Russians back, but it could deny them major gains, sapping their resources and will to fight. Western military assistance, especially the provision of arms and training, will be critical for sustainment. But so will domestic factors such as the return of Ukrainian refugees, the recovery of the country’s economy, and the emergence of a Ukrainian resistance in Russian-occupied areas. Sustaining the fight against Moscow, in other words, will take political, economic, and military commitment from the Ukrainian people as well as from the United States and other NATO countries. The challenge, however, is that sustainment will become increasingly costly as the war continues and Western countries find it increasingly difficult to muster the political will to uphold their commitments to Ukraine.


Early in the war, Russia gave little thought to sustainment, rushing forward a vast force without setting up supply depots or establishing full air control. As the Ukrainians slowed Russia’s advance, distance and weather compounded Moscow’s logistical problems—and Russian soldiers paid a heavy price. The shift of the fighting to eastern Ukraine has eased some of these logistical challenges for Moscow. The frontlines are now closer to Russia and linked by rail and road to Russia and Russian-occupied territory. But Moscow’s initial blunders burned through many of its resources, undercutting Russia’s ability to resupply and sustain its forces even in the east. Unable to reliably import supplies and parts because of Western sanctions, Moscow is now digging deep into its Soviet era stockpiles for weapons such as mines and tanks.

Russia is having even more trouble shoring up its manpower. Estimates of casualties vary widely and are likely distorted by political calculations on both sides, but Moscow is clearly struggling to reinforce its fighting forces. Russia’s lower house of parliament, the Duma, recently removed the upper age cap for contractual service in the Russian army in order to expand the pool of eligible recruits that can be sent into battle.

For their part, the Ukrainians are also showing signs of strain. Before Russia’s invasion in February, Ukraine had been making significant progress in reforming its military, increasing civilian control, limiting corruption, streamlining command and control, and modernizing its force structure to better align with NATO’s model. These and other changes helped Ukraine fend off Russia’s initial assault, thwarting the Kremlin’s ill-fated plan to take Kyiv and other major Ukrainian cities. But the reform process was in no way complete when Russia invaded, and it has understandably slowed in the midst of a major war.

In a conflict that is likely to end with a negotiated settlement, sustainment could provide vital leverage for Ukraine.

One critical element of sustainment involves moving forces to the locations where they are needed most and reinforcing or replacing depleted units. These functions become harder as a war drags on and military and civilian casualties mount. The forces stationed in the east of Ukraine are some of the country’s best and most experienced fighters, but they have taken the brunt of the losses ever since Russia began concentrating its attack on the Donbas. Ukrainian leaders had been relatively tight-lipped about the scale of Ukrainian losses until last month, when a senior presidential aide revealed that between 100 and 200 troops were being killed every day.

At that rate, retaining the manpower needed to prevent further territorial losses, let alone win territory back, will require significant reinforcements. And Ukraine’s troop reserves are not infinite. Indeed, interviews with volunteers who joined the territorial defense forces in western Ukraine paint a dire picture of troops being rushed eastward to the front without adequate training, weapons, or support. Getting reinforcements and supplies to the frontlines has also gotten harder as roads and rail networks have been destroyed in the fighting and as Russia has threatened Ukrainian supply lines in parts of the east, especially now that Ukrainian forces have made a tactical retreat from the beleaguered city of Sievierodonetsk.


It is clear that Ukraine needs additional Western military support. The country had limited defense production capacity even before the war, and over the last four months Russia has destroyed or captured much of that capacity. Russia has also targeted many Ukrainian ammunition depots. As a result, Ukraine’s sustainment effort will hinge in part on the resupply of Western ammunition, rockets, drones, and other heavy equipment.

Perhaps unsurprisingly, the U.S. defense industry has endeavored to make this possible.  Lockheed Martin, which manufactures the much-vaunted Javelin antitank missiles that Washington has supplied to Ukraine, promised in May to nearly double its annual output to meet demand, albeit over the next few years. Raytheon, meanwhile, has been supplying Ukraine with Stinger antiaircraft missiles. But even U.S. defense giants have limits. Raytheon has already said it will not be able to increase production of Stingers until 2023 because it lacks parts, and some U.S. lawmakers have expressed concern that arms shipments to Ukraine are depleting U.S. stockpiles of these weapons. The U.S. Department of Defense is clearly facing its own sustainment demons, struggling to increase the production of these and other supplies because of pandemic-related shortages and generally lackluster defense industrial capacity.

Just as important as resupplying weapons and ammunition is training the Ukrainian soldiers and civilian volunteers who are using this equipment. Advanced weapons systems delivered by the United States and other NATO countries are only useful if Ukrainian soldiers know how to use and maintain them—skills that are difficult and take time to learn. The U.S. Army’s Javelin training course is 80 hours long, for example, while training on a mobile artillery rocket system made by Lockheed Martin can take up to two months. (The first of these  Lockheed Martin systems was confirmed to be in use in Ukraine last week, suggesting that training is moving faster than expected.)

It is clear that Ukraine needs additional Western military support.

Since U.S. military advisers had to withdraw from Ukraine to avoid the possibility of direct confrontation with Russian forces, training on these and other systems must take place outside the country. Ukrainian soldiers have traveled to U.S. bases in Germany and Poland to learn how to operate artillery, air defense radar systems, drones, armored personnel carriers, and  according to some reports, even sophisticated electronic warfare systems supplied by the United States and other countries. These troops will now be able train their fellow soldiers back in Ukraine. But efforts such as these impose difficult tradeoffs. On the one hand, they enable Ukraine to employ new military capabilities. On the other, they take skilled soldiers out of the fight at precisely the moment when manpower needs are at their most acute.

Then there is the maintenance challenge. Artillery and radar systems, as well as other advanced military equipment, require specialized and often highly technical training to maintain. Ukrainian troops have received some of this maintenance training in Germany and Poland—for instance, on artillery pieces known as M777 howitzers. But maintenance of even these relatively basic weapons is complicated by the fact that they are manufactured using the imperial measurement system while Ukrainian wrenches use the metric system. This means that American-made wrenches must accompany every American-made howitzer—one more complication in an already intricate and fragile supply chain that flows from Poland overland into western Ukraine and then to the frontlines in the east of the country.


The strength of Ukraine’s sustainment effort will depend in part on what happens in Washington and other Western capitals. Since January 2021, the United States has spent $6.8 billion on security assistance to Ukraine. U.S. President Joe Biden announced an additional $40 billion last month, half of which will be dedicated to military assistance. Other NATO members have also provided substantial support, including Estonia, Slovakia, Turkey, and the United Kingdom. And earlier this month, European leaders met with Ukrainian President Volodymyr Zelensky in Kyiv, promising continued aid and affirming their support for Ukraine’s accession to the EU.

How long this support lasts will depend on the public mood in Western countries. Support for Ukraine remains relatively high in the United States, in European countries, and in allied countries such as Australia, Japan, and South Korea. Yet popular opinion about the war is more mixed in parts of Southeast Asia, the Middle East, and Africa, where Russia has more influence and where it has concentrated its disinformation campaigns. If inflation, food shortages, and supply chain disruptions persist, countries in these regions could push to scale back sanctions on Russia or reduce aid to Ukraine.

But just as important as the international climate is what happens in Ukraine itself. Hundreds of thousands of Ukrainian refugees have returned home in recent months. Repatriation on this scale could initially strain food and health resources, but it could also help revive the economy and labor market, facilitate the movement of supplies and medical support to the frontlines in the east, and provide a morale boost to the nation as a whole. Already, commercial goods have begun to move more freely in western Ukraine, indicating that the overall logistical situation is improving. Getting the west of the country—and especially cities such as Kyiv—up and running again will help relieve some of the food and medical shortages in the east. Finally, reports of increased resistance and sabotage in Russian-occupied areas suggest that Ukrainians could yet disrupt Moscow’s supply lines—thereby eroding its ability to sustain the offensive.

As the war in Ukraine has transformed into one of attrition, the importance of sustainment has been elevated, perhaps above all else. Although a decisive military victory in which the Ukrainians expel Russian forces from their entire territory seems increasingly unlikely, Kyiv could still stymie Moscow’s progress and strengthen its position for future negotiations by continuing to surge reinforcements and supplies to the frontlines. If the past four months of war have revealed anything, it is that underestimating Ukraine is a mistake. The United States and its allies must do their part to help Ukraine sustain the fight.

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