Franz-Stefan Gady and Michael Kofman on what Ukraine must do to break through Russian defences

COMBINED-ARMS WARFARE is a deadly ballet choreographed to overwhelm the defender by integrating different combat arms, such as infantry and artillery, and services, such as ground and air forces. Its origins lie in the last two years of the first world war. After years of stalemate, the German Imperial Army adopted innovative tactics to break through the layered Allied defences of the western front and thus out of the attritional deadlock.

This novel approach was not enough to win the war, but it changed the course of warfare. Before 1917 most operations were sequential. Days of artillery fire on a trench gave advance warning of an attack. When the fire paused and infantry went over the top, soldiers would be mown down. The same attack in combined-arms fashion would involve brief artillery fire on the enemy position, combat engineers clearing obstacles such as mines and barbed wire, and soldiers advancing under covering fire immediately afterwards.

Having recently returned from a field study in Ukraine, we are convinced that although Ukrainian forces can fight in a combined-arms fashion, they cannot yet do it at scale. The premise of Ukraine’s counter-offensive was that a combined-arms assault could breach Russian lines and enable a breakthrough to the Sea of Azov. Western-trained and -equipped brigades, with others, could engage in manoeuvre warfare—using forces to break through the enemy’s lines, disorienting them, rather than just wearing them down with attrition. If successful, this would allow Ukrainian units to move deep into the Russian rear, penetrate supporting areas and cause the front line to collapse.

Previous battles in Ukraine had given grounds for caution. Ukrainian forces struggled to co-ordinate attacks on a large scale or to synchronise use of forces, often resorting to long phases of attrition, as in Kherson last year. The initial breaching attempt during Ukraine’s summer offensive showed that many of these problems remain.

The offensive quickly resorted to extensive use of artillery and small-scale assaults by infantry units, fighting from tree line to tree line. Progress is slow because much of the battlefield is densely mined, with anti-tank guided missiles, attack drones and aircraft posing further problems. In the south Ukraine has been drawn into an artillery-dominated war of attrition. The situation around Bakhmut, farther north, is better, largely because the Russian forces there are not as entrenched and the geography of the battlefield is more favourable to Ukraine. Still, there, too, progress has been slow and costly.

Ukraine is struggling to conduct effective combined-arms operations largely because of deficiencies in two areas: training and experience.

Start with training. The problem is both a lack of it and the wrong sort. Over the course of the war Ukrainian forces have lost a large number of their best personnel, with many units on the line unable to rotate out. Combined-arms warfare requires significant time for training, not only to learn how to use equipment but also how to operate effectively as a unit. New units with a few months of training in the West may perform well in individual combat tasks but still lack cohesion.

The new brigades have been unsuccessful not only because they had little time to develop this cohesion, but also because they have not been trained the way they need to fight. Ukrainian soldiers’ ability to master Western tech quickly led to misplaced optimism that the time it takes to develop cohesive fighting units could be short-circuited. Putting these units in the vanguard of a difficult assault, instead of more experienced formations, now looks like a mistake that reflected the prioritisation of Western kit over time in the field.

This war also reinforces the importance of experience. Ukraine’s army is now one of the most experienced in the world, but it still lacks experience co-ordinating offensive action on a large scale. What on paper is an attacking brigade of several thousand men is, in practice, a couple of reinforced companies of no more than a few hundred men each—a smaller force that struggles to establish superiority over entrenched defenders. Although Ukraine can conduct combined-arms assaults at the level of a platoon, this begins to come apart when attempting to scale up to the level of a company or battalion.

Ukraine’s armed forces remain uneven because of losses and several waves of mobilisation. Experienced brigades can correct artillery fire and conduct reconnaissance and suppress enemy positions in advance of an attack. Newer units are unable to put those pieces together even when provided with the best Western equipment.

Even if Ukraine were able to fix all these tactical issues, it would still struggle to overcome Russian defences without more mine-clearing equipment, short-range air defence, air power and a significant advantage over Russia in stocks of artillery ammunition. Ukraine’s forces are highly motivated but face a daunting task against minefields, entrenchments and competent Russian defenders.

A Ukrainian force that has struggled to co-ordinate the different parts of its ground force will find it even harder to integrate them with air power, which Ukraine currently lacks. Integrating Western air power—Ukraine hopes to get American F-16 fighters soon—and using it effectively is likely to take years. It would be rash to pin too much hope on it when it arrives: having air power does not guarantee air superiority, which is not easily gained or maintained on a battlefield where advanced air defences are plentiful and the opponent’s air force outnumbers yours.

Working to improve Ukraine’s ability to employ combined arms in offensives will take time, too. Ukraine’s victory will not be secured by any single capability or weapon, but by effective use of force, better training and sustained Western support.

Ukraine’s offensive is far from over and attrition has served it well in the past. A new wave of attacks by second-echelon forces is now testing the Russian defence to see if attrition has had the desired effects. The West is best served by backing Ukraine’s way of war, by exploiting its advantages in defence-industrial capacity (including ammunition production) and the quality of its weapons. Help Ukraine to fight the way it fights best. ■

Franz-Stefan Gady is the founder and CEO of Gady Consulting and a consulting senior fellow with the Institute for International Strategic Studies. Michael Kofman is a senior fellow at the Carnegie Endowment.