This week, Russian forces made their most significant breakthrough in nine months — but at a heavy cost.

They took the small Eastern Ukrainian city of Avdiivka, ending a brutal battle that has been raging since October. While undoubtedly a setback for Ukraine, the fall of Avdiivka was not an unambiguous victory for Russia.

Ukrainian military commanders estimate that 47,000 Russians were killed or injured in the battle, which is significantly higher than the pre-war population of Avdiivka of around 32,000. The estimated death toll in the battle, 17,000, would be higher than the Soviet army’s during the 10-year war in Afghanistan.

Those numbers are impossible to verify and very possibly exaggerated, but there’s no doubt the losses were exceedingly high and that this is a point of sensitivity for the Russian government. (This week, a pro-war Russian military blogger died reportedly by suicide after being forced to remove a post criticizing military commanders for the high casualties sustained in the battles.) Britain’s Ministry of Defense also estimates the Russians lost more than 400 tanks in the battle.

Given those losses, it’s natural to wonder whether Avdiivka — not even one of the larger cities in Donetsk province, much less Ukraine — was a Pyrrhic victory for the Russians.

Yes, in both Bakhmut and Avdiivka, the Russians demonstrated that with enough time, artillery ammunition, and human lives, they can take a small Ukrainian city, almost entirely demolishing it in the process.

But is this a sustainable strategy for victory over the second-largest country, in terms of land area, in Europe?

“I do not think it’s sustainable, but it is what I think that they’ll do,” retired Lt. Gen. Ben Hodges, former commander of the US Army in Europe, told Vox, saying the war would come down to whether Ukraine could count on continued Western support. “They’ll do it because they can see that we are starting to waver.”

The key factor when it comes to understanding Avdiivka is not so much size, location, or strategic significance, but timing. The loss comes at a time when international support for Ukraine, particularly in the United States, is starting to fade. It raises stark questions about what it will take from Kyiv and its international backers to keep Ukraine in the fight.

The Ukrainians may be able to stabilize the front line in the coming months, but without significant additional support, Avdiivka is unlikely to be the last city to fall.

How significant of a victory is Avdiivka?

Avdiivka was “not a mere symbolic Russian victory,” said Franz-Stefan Gady, an Austrian military analyst with the Center for a New American Security (CNAS), who travels regularly to the front lines in Ukraine.

The town lies less than 10 miles from the Russian-held city of Donetsk, the capital of the self-proclaimed Donetsk People’s Republic. The loss will put the city much farther out of range for any future Ukrainian counteroffensive. “Ukraine is losing an important strongpoint that anchored Ukrainian defenses in the area. It could potentially open up new avenues of attack for Russian forces,” Gady added.

Analysts also pointed out, though, that given the exhaustion of Russian troops after taking the city, they would be unlikely to be able to press further into Ukrainian-held territory. In a recent assessment, the Washington-based think tank Institute for the Study of War said Ukrainian forces would likely be able to set up new defensive positions just a few miles beyond the city, forcing the Russian offensive to culminate here.

“Battlefield results are measured in the ability to turn a local success into a bigger one,” Mykola Bielieskov, an analyst with the Kyiv-based National Institute for Strategic Studies, told Vox. “The Russians won’t be able to do that after pushing us out of Avdiivka. They lack reserves and have been exhausted from a five-month fight.”

But even though Kyiv and its foreign backers don’t publicize Ukrainian casualty numbers, it’s clear the Ukrainians took heavy losses as well. A recent New York Times account based on interviews with Ukrainian troops describes a chaotic retreat from the city in which hundreds of Ukrainian soldiers may have been captured. Unverified images on social media show some of these prisoners being executed. The outcome is likely to contribute to already serious morale problems at the front and add to Ukraine’s difficulty in recruiting new troops.

Avdiivka was a long and draining fight for both sides, and though it’s likely the Russian losses in the battle were far greater, Ukraine may have less of an ability to absorb those losses.

Ukraine’s hunger for shells

The battle for Avdiivka may have taken place in the fields surrounding the city, but the road to defeat may well have started in Washington, DC.

Experts have been warning for months that unless the US Congress allocates new military aid to Ukraine — the last American aid package was sent in December — Ukraine would start to lose the ability to defend the 1,500-kilometer front line.

The biggest problem is artillery ammunition: Last summer, Ukraine was firing more artillery shells than Russia per month. Now with supply shortages, it is firing less than a fifth of what the Russians can put out, according to Britain’s Royal United Services Institute.

“If you don’t have shells, then courage alone will not be enough to win,” said Yehor Cherniev, a member of the Ukrainian Parliament and deputy chair of its national security committee. Cherniev said it was “cynical” of opponents of military aid to point to losses like Avdiivka as evidence that Ukraine can’t win. “First, they don’t give Ukraine shells, and then they lament that it has lost a populated area and claim that Russia cannot be defeated,” he said.

The White House has placed the blame for the defeat squarely on congressional Republicans. National Security Council spokesperson John Kirby told reporters in a call on Monday that Avdiivka was not lost because Ukrainian troops lacked skill or training: “It was because of congressional inaction. We’ve been warning Congress that if they didn’t act, Ukraine would suffer losses on the battlefield, and here you go. That’s what happened this weekend.”

Avdiivka may be only a sign of things to come if aid does not resume.

Last week, the Senate overwhelmingly passed an aid package that included military funding for Ukraine as well as Israel and Taiwan, and though previous aid packages have passed with substantial majorities, it’s not clear if the bill will even come up for a vote in the GOP-controlled House, given former president and presumptive Republican nominee Donald Trump’s public opposition to more aid.

Asked by Vox if Ukraine could continue to rely on US support for the long term, Sen. Chris Murphy (D-CT), a leading advocate of Ukraine aid, replied, “I don’t know. We were all together just a year ago, but Trump is causing Republicans to walk away from Ukraine. I think everybody should be worried. This [US] election will be definitive as to whether or not Ukraine survives.”

Republican critics of aid, such as Sen. J.D. Vance (R-OH), counter that no amount of US aid could turn the tide given Russia’s overwhelming advantages in terms of soldiers and industrial capacity.

“The West doesn’t make enough munitions to support an indefinite war. Ukraine doesn’t have enough manpower to support an indefinite war,” he told Politico on the sidelines of the Munich Security Conference this week.

It is true that Ukraine’s forces face significant personnel shortages, and that the government has been reluctant to pass controversial legislation that would expand conscription and crack down on draft dodging.

“They have failed to make the necessary political decisions to do this,” said Hodges. “I think not only is that a problem for them on the battlefield, but it also will begin to undermine some Western support.”

The task ahead

Stabilizing the front lines after the withdrawal from Avdiivka will be an early test for Gen. Oleksandr Syrskyi, who took over as commander of Ukraine’s armed forces this month. In recent days, the Russians have been concentrating forces for what appears to be an attempt to break through Ukraine’s lines in another area by retaking territory around the southern city of Robotyne, one of the rare successes of Ukraine’s summer counteroffensive.

“One of the problems with the end of Ukraine’s counteroffensive is that much of the terrain that was seized was not particularly defensible terrain,” the analyst Rob Lee wrote on Twitter.

CNAS’s Gady said it’s likely there could be “more tactical withdrawals in the coming weeks,” as Ukrainian commanders work to stabilize the situation.

Beyond the next few weeks, 2024 is likely to be a rebuilding year for Ukraine, as they restore battered units, train new ones, and wait for more aid to arrive. European ammunition production is finally starting to ramp up, though at a much slower rate than Ukrainians hoped last year.

The US reportedly has artillery systems and ammunition ready to send to Ukraine immediately if and when Congress approves funding, and is also leaning toward supplying long-range ATACMS missiles, which it has so far declined to send, and which the Ukrainians say will give them a better ability to disrupt Russian supplies and logistics.

As bleak as the picture has often been on land in recent months, the Ukrainians have been having better luck on the Black Sea, where the bulk of the Russian fleet has been pushed back by Ukrainian missile and drone strikes and where Ukrainian grain exports by ship are back to near pre-war levels.

As promising as those developments may be, this is ultimately a war over territory that comes down to Ukraine’s ability to defend it.

Russia has its own supply issues, which forced it to recently begin purchasing mass quantities of ammunition from North Korea, and has also been reluctant to call a second mass mobilization to bring more troops to the front. But Russia’s ability to sustain heavy losses also shouldn’t be underestimated. A recent analysis from the International Institute for Strategic Studies estimated that even after losing around 8,800 fighting vehicles in the war so far, Russia will probably still be able to sustain its assault on Ukraine at current attrition rates for another two to three years.

It’s clear that this will be a much longer war and a contest of industrial capacity and political will as much as military maneuvers. But even getting to that marathon will require Ukraine getting past a very difficult period in the coming months.

Gady said a complete collapse of Ukraine’s defenses was not entirely out of the question, but still unlikely: “There are going to be a couple months where the situation is really dire for Ukraine, but I think they can hold.”

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