NATO leaders have been worried by the heavy casualties and massive ammunition usage in Ukraine.
"The scale of this war is out of proportion with all of our recent thinking," NATO's top general said in January.
The heavy casualties and massive ammunition consumption seen during the war in Ukraine has top NATO commanders worried.
NATO was created in 1949 to stop a massive Soviet invasion of Western Europe, and it has added new members since the end of the Cold War, but many of its militaries shrank in the decades after the Soviet threat disappeared. Now the scale and intensity of the fighting in Ukraine has raised questions about the alliance's ability to fight a big-unit war against Russia.
"Scale, scale, scale," US Army Gen. Christopher Cavoli, NATO's Supreme Allied Commander Europe, told a Swedish defense conference in January. "The magnitude of this war is incredible. The Ukrainians have 37 frontline brigades, plus dozens more territorial brigades. The Russians have lost almost 2,000 tanks. If we average out since the beginning of the war, the slow days and fast days, the Russians have expended on average well over 20,000 artillery rounds per day."
"The scale of this war is out of proportion with all of our recent thinking," said Cavoli, who is also head of US European Command. "But it is real and we must contend with it."
One lesson is the importance of an adequate defense industrial base capable of providing the necessary equipment and supplies to satisfy the voracious appetite of large-scale, high-intensity warfare. The US, Russia, and Europe are already scrambling to ramp up production of artillery shells after letting their munitions stockpiles and factories run down after the Cold War.
"Production capacity remains vital, absolutely vital," Cavoli said. "A healthy and elastic defense industrial base is just as important" as the number of troops.
Cavoli also took aim at the belief - until recently touted by Germany and other countries - that soft power has become a substitute for military power.
"Hard power is a reality," Cavoli said, adding that diplomacy, cyber-warfare, and economic strength are important, "but the great irreducible feature of warfare is hard power, and we have to be good at it."
"If the other guy shows up with a tank, you better have a tank," Cavoli said.
Interestingly, Cavoli pointed to Ukraine's surprising battlefield successes as evidence that "precision can beat mass." But there's a catch: It takes time for quality to beat quantity, and "that time is usually bought with space. To use this method, we need space to trade for time. Not all of us have that, and we have to compensate for this in our thinking, our planning."
For Russia's smaller neighbors that lack strategic depth - such as the Baltic States - that's an admission that NATO may not have time to come to their rescue should Russia invade.
As for NATO, the alliance never did fight the war it dreaded against the Soviet Union. But after the Cold War ended, the NATO did engage in several military operations.
NATO aircraft conducted bombing operations in Serbia in 1999 and Libya in 2011. The alliance also sent troops on peacekeeping missions in Bosnia and Kosovo and to fought alongside US forces in Afghanistan.
But these were small operations involving limited numbers of troops, aircraft, and munitions. Even then, it became clear that NATO - which has expanded from 12 founding members to 30 members today - was dependent on US support. In Libya, for example, NATO air forces ran short of precision-guided bombs after the first month.
That Moscow is buying artillery shells from North Korea suggests that Russia's military is no shape to fight NATO and Ukraine. However, NATO's frantic attempts to scrounge up weapons and ammunition for Ukraine shows the alliance doesn't have much depth to its arsenals.
The US is probably the best prepared for a long war, and even then, America's defense industry will need years to ramp up production of artillery shells. Big war is something that no one wants, but Ukraine is a reminder that it is a possibility that cannot be ignored.
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.