Ukraine at last has all the Abrams tanks the US promised. Now the question is how best to use them.

• Ukraine has received all 31 of the formidable M1A1 Abrams tanks promised by the US.
• Current battlefield realities, like the lack of tank-on-tank fighting, could limit the potential uses.

Ukraine has finally received all the M1A1 Abrams promised by the US, but with a slogging counteroffensive and tough winter on its way, Kyiv will have to figure out how best to employ the tanks in the short-term — and keep them prepared for what's next on the battlefield.

Part of that means embracing the current realities of the war, in which tank-on-tank fighting is limited and dense Russian minefields have slowed down the advances of heavy armor and vehicles.

"The Abrams', they're useful, great tanks," said Mark Cancian, a senior advisor with the Center for Strategic and International Studies and a retired US Marine Corps colonel, "but the impact is going to be limited, and what impact they have is going to be very tactical."

The first batch of Abrams arrived in late September, Ukrainian President Volodymyr Zelenskyy announced at the time, immediately adding a formidable force to Kyiv's counteroffensive. Then, earlier this month, US military officials confirmed the delivery of all 31 Abrams promised by the Biden administration earlier this year.

The M1A1 Abrams has garnered an intimidating and fearsome reputation — in the Gulf War in the early 1990s, these tanks earned a reputation as fast and maneuverable armor-shredding machine. And while the US Army now operates the M1A2, that doesn't mean the A1's exactly archaic.

"Although they are not the newer model, the M1A2, they still have a strong track record of defeating Soviet-era armor. They offer a range of practical advantages including higher mobility, better protection, night vision capabilities, more accurate firepower, and greater range," Olivia Yanchik, a program assistant with the Atlantic Council's Eurasia Center, told Insider.

But don't expect to see many showdowns with Russian tanks. Although the Abrams was designed to be a tank killer, tank-on-tank warfare has been quite limited so far in the war. Land warfare experts at the Royal United Services Institute said earlier this year that "tank-on-tank engagements have become relatively rare." Russian minefields have held Ukraine's armor at bay, while artillery and anti-tank missiles threaten the vehicles that do advance. While that's not to say they don't happen, Ukraine's war isn't shaping up to offer tank duels the Abrams was designed for.

When Ukraine launched its long-anticipated counteroffensive in June, troops quickly ran into fortified Russian defenses carved into Ukraine's east and south full of devastating landmines, anti-tank ditches, and dragon's teeth.

The obstacles, such as anti-tank mines stacked on top of one another to maximize destructive potential, sometimes forced Ukrainian troops to abandon Western armor and proceed forward on foot. And when Ukraine initially tried to clear minefields, they faced Moscow's Ka-52 attack helicopters and artillery, which did massive damage.

Since then, Ukraine's made some progress breaching Russian defenses in the south near Zaporizhzhia, mainly relying on infantry to lead the charge and clear the way so that tanks and artillery can come forward. Some videos show Ukraine's tanks blasting Russian positions to assist with infantry assaults, while others demonstrate them providing suppressing fire as foot soldiers make their way past landmines. Mines are just one of the many threats tanks face, including drones, anti-tank missiles, and artillery.

With the Abrams, that tactic wouldn't change much, at least in the short term. "Given the density of minefields close to Russia's first defensive lines, tanks such as the M1A1 Abrams alongside other modern Western armor are restricted in their ability to play prominent roles in offensive operations," Yanchik said. "If Ukraine is able to consolidate its position beyond Russia's initial line of defense however, these tanks will be integral in pushing into less heavily fortified areas."

That could be where the Abrams shines brightest. "Now, if the infantry makes a breakthrough," Cancian told Insider, "then they might be able to open up enough of a gap that you can really push the tanks through and then use all of their capabilities."

The other problem is Ukraine only has 31 Abrams, a small fraction of its entire tank force, which includes other Western armor such as UK-provided Leopard and Germany's Challenger, as well as Soviet-era tanks, which are the bulk of their forces. And maintaining the Abrams — taking care of its powerful but needy engine, which has sometimes been referred to as a "jet engine," and keeping spare parts and fuel readily available — will also limit how and when the Abrams is used.

With winter on the horizon, and potential for a Russian offensive, Ukraine will also have to decide the best role for the Abrams in the longer term. Zelenskyy has vowed troops will continue to push against Russian defenses throughout a wet autumn and cold winter, although it remains to be seen if weather will slow down offensive movement as it did last year. Right now, it appears as though there could be two options: employing the Abrams this winter to bolster the fighting, or reserve them for a counteroffensive next spring.

"I can see both approaches," Cancian said. "I think this links to a much broader question, which is Ukraine's theory of victory, and how are they going to win this war?" He added that with the counteroffensive bogged down, Ukraine could either "keep grinding away through the winter" or "wait, build their strength, and launch a new counteroffensive in the spring."

The answer to that, Cancian told Insider, "will drive how they use the Abrams."

If they do keep up offensives through the winter, expect to see the Abrams in full use, as it relieves other tank units that have been fighting since summer. And if that's the case, the Abrams wouldn't have much trouble with eastern Europe's infamous mud season, when the ground turns to sludge, as it was designed for combat with that environment in mind. Especially in a drier area like southern Ukraine — where Kyiv's troops could continue attempting to bust through Russian defenses and push all the way down to the Sea of Azov, severing Russian-held territory in the process — the Abrams may not even encounter mud in the first place.

Regardless of how Ukraine uses the Abrams next, its long-term success may be more reliant on what other Western weaponry is delivered. It most recently struck with new long-range missiles, the secretly acquired MGM-140 Army Tactical Missile Systems (ATACMS) that hit Russian bases behind lines. The US had long debated sending ATACMS to Ukraine, expressing hesitancy because of their range and ability to strike within Russia.

But with Ukraine finally getting ATACMS, which it long had atop its wishlist, there's plenty of potential for future Western assets to be transferred. And that could directly impact how the Abrams is used.

"How the Abrams will be useful later on, of course, depends on whether Ukraine is given what it needs to win," Yanchik said. "Ukraine is already rapidly integrating Western systems into its overall military profile and is becoming more compliant with NATO architecture by the day. In the future, this will enable Ukraine to engage in broad NATO exercises for building and maintaining force readiness."