The euphoria that was detectable when I visited Kyiv a year ago, just as the Ukrainians forced a major Russian retreat from Kharkiv, has largely faded, replaced by defiant exhaustion. Soldiers back from the front line are weary, and they do not mind admitting it. More was expected of this summer’s counteroffensive than they have been able to achieve.

The principal problem is that relatively raw troops, without air superiority, have been advancing against well-fortified Russian positions. The time the West took agonizing about which weapons to send Ukraine was used by the Russians to dig in and lay mines. Some Ukrainian commentators regard the supply of military hardware to Kyiv as — by design — enough for their side not to lose, but not enough for them to win. Example: the belated US decision to send Ukraine a limited number of long-range ATACMS missiles, just as the Ukrainian offensive is drawing to a close.

Despite Ukraine’s lack of meaningful progress, there has been much to admire about the Ukrainian way of war this summer. As one Ukrainian general told the conference I was attending, “Not a single unit goes to the battlefield without a UAV [i.e. drone] of its own.” Each exploding drone can destroy an estimated $1 million of enemy military equipment. Ukraine has become an experimental laboratory for the war of the future.

However, no amount of technology can entirely compensate for the lack of experience of the troops themselves. The chief of staff of Ukrainian forces on the eastern front told us that in recent days it was the Ukrainians who were on the defensive against Russian attacks on Bakhmut. Ukraine’s deputy minister of defense similarly noted that the Russians are seeking to take back some of the territory they lost last fall

Ukraine’s Western allies are watching all this with disquiet. In the words of Victoria Nuland, US acting deputy secretary of state, “We haven’t seen defenses like the Russians’ in a hundred years” — a pardonable exaggeration. “This is a long fight,” she told a mostly Ukrainian audience on Sept. 9.

General Christian Freuding, director of the joint planning and command staff of the German Defense Ministry echoed her words. “No one expects the war to be over within six months,” he said. The German government is planning with a “time horizon of 2032.” The German definition of victory, he said, is to restore the territorial integrity of Ukraine to its 1991 borders. That is also the position of the Ukrainian government. The hard question is how this can be achieved.Bob Seely, a British Conservative MP who has recently visited the front line, reported that the Ukrainians have been suffering heavy casualties. “For every 75 meters that are retaken,” he estimated, “a Ukrainian soldier dies.” A great deal of the killing is being done by 120 mm mortar shells. Seely also noted the increasing effectiveness of the Russians’ ZALA Lancet drones.

Wars of attrition do not favor the smaller combatant. It is hard to see how many more offensives Ukraine is capable of mounting between now and 2032 — or indeed between now and this time next year.