Russian failures in Ukraine are forcing Moscow to give up on one of the biggest Putin-era military reforms

• Moscow's ambitions for a quick, sweeping victory in Ukraine were foiled soon after it invaded.
• In the 19 months since Russia attacked, its forces have faced logistical and leadership challenges.

As Russian troops massed along Ukraine's borders in late 2021 and early 2022, some Western experts warned that Vladimir Putin's army was not the army of Josef Stalin.

The bulky Red Army divisions of World War II and the Cold War, each of which numbered about 10,000 troops, had been replaced in the 2000s by smaller, more agile battalion-size formations of between 500 and 1,000 troops — an effort to create a force more like that of the US and other Western armies. Or so the theory went.

The performance of those units in Russia's invasion of Ukraine in February 2022, where they faced outnumbered and outgunned Ukrainian defenders, was a fiasco. The feared Battalion Tactical Groups, or BTGs, proved as unwieldy as Russia's divisions were rigid.

Now Russia is returning to division-size formations to create more resilient formations that can sustain intense attritional warfare like that in Ukraine — at the cost of agility, according to Olesya Tkacheva, an expert on the Russian military at the Brussels School of Governance.

"Mobility is being sacrificed in exchange for resilience," Tkacheva said during an online event hosted by the Wilson Center in Washington DC.

Despite the hype, the BTG was hardly a revolutionary concept. The German Army in World War II routinely formed combined-arms battlegroups ("kampfgruppen"), as did the US Army's task forces. Sometimes it was deliberate, and other times it was out of desperation as commanders scraped together whatever was available for a given mission.

The Red Army in World War II tended to fight as separate branches — infantry, armor, and artillery — that were only combined just before a battle, two analysts with the US Army's Foreign Military Studies Office noted in an April 2022 report for Britain's Royal United Services Institute think tank.

The Soviet Army experimented with various combinations of units, which formed the basis for the BTG in the post-Soviet era.

"The most common BTG variant is based on a motorized rifle battalion with an attached tank company, self-propelled howitzer battalion, air defense platoon, engineer squad, and logistic support," the RUSI report said. BTGs were composed of professional contract soldiers, who are generally more capable, competent, and motivated than the sullen conscripts that still hamper Russia's army today.

BTGs were intended for the new — at least for Russia — concept of expeditionary warfare. This required small units that could remain at a higher state of readiness, be deployed quickly, and be somewhat self-sufficient all-arms formations. The Russian military's failure to deploy and operate effectively in Georgia in 2008 had driven home for Moscow the need for such a force, which it has been able to put to use, most notably in Syria in the mid-2010s.

"Mobility and deployability outside of Russia's territory was one of the key strategic objectives," Tkacheva said of the thinking behind the embrace of BTGs.

Before World War II, the British Army was configured as an expeditionary force for policing its empire, but when it encountered heavily armed German forces, its equipment proved inadequate. Russia had the same problem when its BTGs had to engage in large-scale conventional warfare in Ukraine.

"Those battalion battle groups turned out to be highly unstable," Tkacheva said. "They were not resilient. They lost a lot of equipment and [had a] high casualty rate. As a result, the Ministry of Defense announced that they're switching back to the Soviet-style organization of the Russian Armed Forces, which is based on divisions."

Other experts point to issues with the entire Russian force structure. A few high-readiness battalions can't compensate for the low-readiness conscripts that make up about one-third of Russia's army.

Lack of manpower also resulted in BTGs being smaller than designed and having fewer infantry than needed, even though they had plenty of armored vehicles. It also meant there were insufficient forces to rotate tired and depleted units out of the line.

"The Russian military is well-suited to short, high-intensity campaigns defined by a heavy use of artillery," Michael Kofman and Rob Lee, both experts on Russia's military, wrote in June 2022.

By contrast, that military is poorly designed for a sustained occupation or for a grinding war of attrition, either of which would require a large share of Russia's ground forces — exactly the conflict the Kremlin now finds itself in.

Switching from battalions to divisions as primary units may be a sensible move, depending on how static the Ukraine conflict becomes. As trench warfare froze the Western Front during World War I, armies emphasized resilience over mobility to endure grinding losses, but when Germany launched a devastating last-ditch offensive in 1918 — a sort of pre-blitzkrieg — their forces lacked the mobility to exploit breakthroughs.

If Russia can repel Ukraine's counteroffensive and the conflict becomes one of trench warfare and limited battles fought over small chunks of ground, then resilient but low-mobility forces will be useful. But if Ukraine achieves a breakthrough, and Russian troops have to maneuver quickly, they may struggle to keep up.

Michael Peck is a defense writer whose work has appeared in Forbes, Defense News, Foreign Policy magazine, and other publications. He holds a master's in political science. Follow him on Twitter and LinkedIn.