This week, the new phase of Russia’s war in Ukraine has taken form. It is a war over control of the Donbas, the eastern Ukrainian region where Russia has been supporting a separatist rebellion since 2014.

Whereas the war — which began with the Russian invasion on February 24 — previously spanned the country, centering on a Russian push to seize Ukraine’s capital and most populous city, Kyiv, its newest offensive is narrowly focused on a region several hundred miles to the east.

“The Russian troops have begun the battle for the Donbas,” Ukrainian President Volodymyr Zelenskyy announced in a Tuesday address.

This is, in one sense, a smart move by the Russians. Its attempt to seize Kyiv in the war’s opening days was decisively repulsed, due not only to Russian incompetence but unusually strong Ukrainian resistance that benefited from defending in tricky urban settings. The terrain in the Donbas — fewer suburbs, more open land — affords the defenders fewer advantages. In the east, Russia can concentrate its forces and move toward battles in which their superior artillery and air force can be used to devastating effect. Territorial successes in the Donbas could blunt the narrative of Russian military incompetence and give the Kremlin a more plausible argument that its war has achieved something real.

Yet Ukraine has advantages too. The forces it currently has in the Donbas are some of its most battle-hardened fighters, having spent the past eight years clashing with Russian-backed separatists. It is getting tremendous amounts of Western aid and still has superior morale and logistics — decisive factors in repulsing Russia’s advances elsewhere. It may numerically match the theoretically much larger Russian army, according to military observers.

For these reasons, the outcome of the new phase is far from clear, even to leading experts on the Ukraine war. In our conversations, they suggested that possible outcomes ranged from Russia successfully seizing control of the entire Donbas to Ukraine actually clawing territory back. The fighting is likely to be long and bloody, no matter where the lines end up being drawn.

Alexei Alexandrov/AP

But the sources I spoke with all agreed on one thing: In the big picture, the outcome in the Donbas might be less important than it may seem. That’s because Russia’s ultimate aim — regime change in Kyiv, or at least forcing Ukraine to submit to a Russian-dominated political future — has been out of reach for weeks. Russia can continue to launch missiles at Ukrainian cities in other regions, terrorizing civilians, but it cannot currently threaten to actually seize those population centers or topple President Volodymyr Zelenksyy’s government.

“Politically, Russia [already] lost the war,” says Michael Kofman, an expert on the Russian military. “When it withdrew from the north, around Kyiv, it eliminated any impetus Ukraine might have for settlement.”

Russia’s offensive in the Donbas, then, is best understood as an effort at limiting the costs of its blunder: a campaign to string together significant enough gains — like the seizure of Mariupol — to soften the blow from its overall strategic defeat.

Russia is shifting to the Donbas because its initial attack failed

There are good reasons for Russia to focus on the Donbas.

Ukraine’s easternmost region, stretching from Luhansk down to around Mariupol in the south, the Donbas directly borders Russia and Russian-held territory in southern Ukraine. Seizing the region’s south would create a Russian-controlled corridor connecting occupied Crimea to Russia proper, a so-called “land bridge” that would make supplying Crimea somewhat easier.

The Donbas’s population has long been more pro-Russian than the rest of Ukraine, though this can be overstated and may well have changed since the war began. The region has been at the center of Russia’s war propaganda, inventing claims of a “genocide” against ethnic Russians in the region to justify the invasion. It is rich in natural gas.

And yet, not a single one of these reasons was sufficient to make the Donbas the center of Russia’s initial invasion. That’s because the goal at first was regime change in Kyiv — Putin’s now-infamous announcement to seek the “de-Nazification” and “de-militarization” of Ukraine.

The new focus dates back to March 25, when the Russian general staff announced their intention to shift offensive combat operations to the Donbas region. At the time, Russian forces were engaged in fighting across Ukraine’s north, east, and south, as you can see on the following map from the Institute for the Study of War (a Washington-based think tank).

Institute for the Study of War

Over the course of the next month, Russia conducted a strategic withdrawal from much of the battlefront, especially around Kyiv and Chernihiv. By April 20, the ISW map shows a shrunken Russian presence focused primarily on fighting in and around the Donbas.

Institute for the Study of War

This shift, first and foremost, reflects the inability of Russian troops to seize Ukraine’s capital and overthrow its government in one fell swoop. “Putin has really started to rethink the strategic aims in Ukraine after the massive strategic failure in Kyiv,” says Rachel Rizzo, a senior fellow at the Atlantic Council’s Europe Center.

Understanding the nature of this failure is vital to understanding what’s happening in the Donbas.

In the Kyiv theater, Russia attempted to plunge troops and armor forward rapidly to seize and/or encircle the capital. These pushes assumed light Ukrainian resistance, which did not end up being the case, and they were undercut by poor logistics and a decision to travel on open roads that created easy opportunities for ambushes.

The Ukrainians took advantage, raiding Russia’s weak supply lines and stymieing the Russians in brutal block-to-block fighting in Kyiv suburbs like Irpin. Russia’s air force, vastly superior to Ukraine’s on paper, was unable to control the skies, allowing Ukrainian drones to wreak havoc on Russian armor.

Sergei Chuzavkov/SOPA Images/LightRocket via Getty Images

The war in the Donbas is different. Russia’s main military objective is cutting off Ukraine’s army in the region, known as the Joint Forces, from the rest of Ukraine by seizing territory to the west of its positions. If the Russian effort is successful, the Joint Forces will lose their ability to resupply and ability to keep fighting — which would allow Russia to consolidate control over a vast swath of the Donbas.

This plan avoids many of the pitfalls that beset Russian forces in the Kyiv region. It mostly requires seizing open terrain from the Ukrainians rather than engaging in urban environments that favor defenders. It entails fighting in a concentrated area, rather than a series of dispersed fronts, which in theory should create fewer vulnerable supply lines. And Russia currently enjoys a measure of air superiority in the Donbas that it didn’t elsewhere.

“If they mass forces, which they’re trying to do now, and they mass them in the right place and they use of a lot artillery and air strikes, they can still have tactical success,” says Rob Lee, a senior fellow in the Foreign Policy Research Institute’s Eurasia Program. “That’s why the Donbas plays into the Russian military’s strength and mitigates some of their weaknesses.”

This is why we should expect a different kind of fighting in the Donbas: fewer raids, more large-scale conflicts between armies. This should favor a Russian force that has always outclassed the Ukrainians in armor, artillery, and aircraft.

Ultimately, the Russian objective here, per some analysts, is to take enough territory to be able to sell its own population — and the world — on the idea that their campaign was a success despite the failures around Kyiv.

Anatolii Stepanov/AFP via Getty Images

If Russia can secure its control over the breakaway republics in the area controlled by pro-Russian separatists — the Donetsk and Luhansk People’s Republics — they can claim to have achieved a pre-war aim of stopping “genocide.”

“They have now put their stake on this being the ‘defense’ of the Donbas,” says Olga Oliker, the International Crisis Group’s program director for Europe and Central Asia.

Ukraine can still win despite Russia’s advantages

If we’ve learned anything in this conflict so far, it’s that theoretical Russian advantages don’t always translate to battlefield success. And there are reasons to think that Ukraine may once again repulse the Russian attack.

The nature of Russia’s plan pits its army against the Ukrainian military elite. The Joint Forces have been fighting in the Donbas since 2014, when Russian-backed separatists rebelled against the government in Kyiv and Russia annexed Crimea. Eight years of war means that they have significant battlefield experience and an understanding of how Russian-trained fighters operate. Given that Russia has made extensive use of untested fighters in this conflict, including poorly trained and equipped conscripts, the Ukrainian advantage in experience could prove decisive.

We also don’t know if Russia has fixed some of the major problems that plagued their campaigns elsewhere in the country. Incompetent logistics and maintenance led to Russian tanks breaking down on Ukrainian roads, out of gas or stuck in the mud. Russian commanders repeatedly employed baffling tactics, failing to concentrate their forces and creating vulnerabilities Ukraine could exploit.

“The biggest question of this upcoming set of battles … is whether or not they have sufficiently learned from the failures of the first month of the war, and are going to put together a coherent, properly resourced effort,” says Kofman.

Chris McGrath/Getty Images

The Ukrainians seem to have two significant and connected advantages: numbers and morale.

On paper, Russia’s military is significantly larger than Ukraine’s. But analysts believe that Ukraine may well be able to field a larger force than Russia in the battle for the Donbas. This is primarily a matter of policy choices: While Ukraine has called up its reserves and recruited civilians in ad hoc militias, Russia has steadfastly refused to adopt a total war footing (its conscription has, so far, been limited).

In military theory, a rule of thumb is that attackers should enjoy a three-to-one advantage over defenders; Russia won’t even approach that, and may suffer numerical disadvantages in some battles. Experts say it would take time for Russia to mobilize substantial reserves from its larger population — time that they simply don’t have, given that the offensive is starting now.

“Because they’ve been so stuck in trying to fight a large conventional war as a ‘special military operation,’ they don’t have access to any large manpower reserves,” Kofman explains. “[By contrast], the Ukrainian military has a tremendous amount of manpower — they have a mobilized reserve.”

Part of the reason for this discrepancy is significant Russian losses in the first phase of the war. But another part is that the Ukrainian population is profoundly committed to the war, creating a large pool of willing fighters who perform more effectively than Russian conscripts. “The Ukrainians can get away with putting accountants who used to shoot at beer bottles out at the dacha because they’re defending their territory,” Oliker says.

While Russian civilians seem to support the war from afar, evidence from the battlefield shows a Russian force suffering from consistently low morale, for reasons ranging from poor training to confusion as to why they’re fighting in the first place.

This gulf in morale has shaped the two sides’ battlefield performance, and will likely continue to do so. Demoralized Russian soldiers are more likely to withdraw when they meet Ukrainian resistance, while the highly motivated Ukrainians are more willing to take risks and lay down their lives to protect their homeland.

How much does the outcome in the Donbas matter?

Both sides have pretty good reasons to believe that they could emerge triumphant.

It’s possible Russia successfully pulls Ukraine into a series of pitched battles in which their aircraft and artillery advantages prove decisive, allowing them to encircle the Joint Forces and seize the entire Donbas. It’s possible that the Ukrainians successfully blunt the Russian attack and mount a counteroffensive, leveraging their manpower reserves and more motivated fighting force to retake parts of the region Russia currently controls. It’s possible they end up in a bloody stalemate, a long war of attrition where the two armies wear each other out over the course of months or years.

Right now, as the fighting is just ramping up, it’s impossible to say which of these scenarios, if any, is the most likely outcome. Too much depends on unpredictable battlefield developments.

Andriy Andriyenko/AP

But at the same time, it’s not clear how much the outcome of the battle will actually end up mattering. In my conversations with experts, each and every one of them said that, in the big picture, Russia has suffered an irreversible defeat in this war.

“The Russian special military operation in Ukraine is already a strategic failure,” Oliker says. “What they wanted out of this was a compliant Ukraine run by people friendly to Russia. This does not seem like a plausible outcome — and, aside from that, their forces have proven to be much less capable than almost everyone thought.”

The initial Russian war aim, as evidenced by its early statements and troop deployments, was to inflict a decisive blow on Ukraine that would transform the country’s political institutions: either imposing a Russian puppet regime or forcing the current Ukrainian leadership to surrender on Russian terms. When Russia withdrew from Kyiv — and not just Kyiv, but most of the northern Ukrainian theater — it de facto conceded that its fundamental war aim was outside of its power.

Even if they do manage to take significant new territory in the Donbas, or impose full control over a bombed-out Mariupol, it’s difficult to imagine these gains outweighing the war’s costs.

The Russian economy has been damaged by sanctions, which could well escalate in the coming weeks. Europe has united against Russia, with historically neutral Switzerland joining the sanctions and both Sweden and Finland moving toward joining NATO. The war has embarrassed Russia’s military and depleted it materially; any territory they occupy in the Donbas will be home to many citizens who hate them, creating the very real prospect of an insurgency backed by Ukraine and the West.

“Win, lose, or draw — the Russian military is likely to be exhausted for some period of time after this coming set of battles,” Kofman says. “The Russian military is very short on manpower, and that’s been evident since the outset of the war. The more territory they capture, the greater the pull on manpower they have, to occupy the territory they seized.”

Alexander Nemenov/AFP via Getty Images

In this sense, the fight for the Donbas is less important than it might seem. The highest-stakes issue in the war seems to have been decided, with Russia on the losing end.

But at the same time, there are real stakes — both in human terms, for the soldiers and civilians who will perish, and also in broader political terms.

The more successful the Russian war in the Donbas is, the easier of a time Putin will have selling his war as a victory to Russia’s citizens. The more territory he controls there, the more leverage he will have at the negotiating table — meaning that he’ll be able to extract more significant concessions on issues like NATO membership from Zelenskyy in exchange for giving back territory taken in the Donbas. (In theory, Russia could benefit economically from controlling the Donbas and its gas reserves; in practice, sanctions, the war’s devastation, and a likely insurgency will probably make it more of a burden than a boon.)

By contrast, another humiliating Russian collapse could do serious damage to Russia’s strategic position. Not only would it make Russian threats of force less credible in other places — who could take their military seriously after such a resounding defeat? — but it could also raise the odds of a political challenge to Putin at home. Zelenskyy would have a dominant hand in peace negotiations, and could achieve terms that would allow for more significant Ukrainian security and political integration with the West.

So while this round of fighting may be less important than the previous one, the stakes are still high.