consumption rate and operational pace," when asked specifically if Ukraine is running low on ammunition and weapons. "It's hard to know," this person said. It's clear that Ukraine is heavily using the artillery the US and other Western nations have provided, because much of it moves in and out of the country for repairs. That blind spot is in part because Ukraine doesn't tell the West everything, Western officials say. And because the fighting is concentrated in such a small area relatively close to Russia, Western intelligence services don't have the same visibility that they do elsewhere. "As you get down to the tactical level, especially in the location where the majority of the fighting is, it's further away from us, closer to Russia, and the forces are more densely packed in very, very close to each other," the senior NATO official said. "So it's difficult to get a good granular picture of the status of fighting occasionally in the east." It's also difficult to predict how Ukraine's military will perform in this pivotal moment because as casualties have mounted, hastily trained civilian volunteers are being sent into the fight, the NATO official added. Their performance under fire is an unknown quantity. "It's one thing to have people available, but the question is, are they ready for the fight? I think you're going to see that as a factor," the official said. Meanwhile, US and other Western officials see no sign that Putin's commitment to prosecuting the costly war has diminished. "In terms of the strategic aims that we judge Putin has vis-a-vis Ukraine, I don't see any signs that those have changed," the NATO official said. "Putin still believes that eventually he will be successful and will either physically control or will gain a form of political control over Ukraine in either significant part or ideally in whole." But even if Putin's commitment remains ironclad, there is a growing awareness that the West's might not be. As the fighting has dragged on, the cost to Western governments has continued to rise. Some Western governments -- including the United States -- have become concerned that the flow of donated weapons to Ukraine has depleted national stockpiles critical to their own defense. "It's a valid concern" for the United States, the senior administration official acknowledged. Then, of course, there is the sting of high energy prices and high inflation. As those costs begin to impact ordinary citizens, in the US and in Europe, and as media attention begins to drift from the day-to-day grind of the fighting, some officials fear Western support for Ukraine may wane. The spokesperson for the Ukrainian military's international legion on Monday derided a "sense of complacency" among Ukraine's military patrons, saying the country needs far more support if it is to defeat Russia's invasion. "There's a certain sense of complacency that seems to have fallen over our Western partners that the arms deliveries that Ukraine has been already provided with are somehow enough to win the war," said Damien Magrou, spokesperson for the International Legion for the Defense of Ukraine, during a news conference. "They are not! They do not come near anything that would be close to enabling us to defeat the Russians on the battlefield."