At its core, a country’s defense strategy is a very expensive gamble. Every year, the United States spends hundreds of billions of dollars on defense—all on the assumption that such investments will allow it to win the next war. Absent a conflict in which the United States is directly involved, policymakers rarely get a window into whether these bets have actually paid off.
One window is when other countries fight a war using U.S. military equipment and tactics—such as the one in Ukraine today. Another example is the 1973 Arab-Israeli War, also known as the Yom Kippur War, when Israel’s near-defeat prompted a thorough reexamination of U.S. weapons and tactics in Washington. Today, Russia’s war once again poses the question whether the United States needs to reexamine the way it prepares for future conflict: not only which weapons it buys, but also how it envisions great-power wars in the 21st century—whether they will be short, sharp affairs or grinding, protracted struggles.
When, in 1973, the United States last had a window into the future of conflict without fighting in one, Israel was caught flat-footed by the surprise attack of an Egyptian-Syrian-led coalition. Although Israel prevailed in the end, the war was a debacle for the Jewish state. Despite having a seasoned military leadership with decades of collective combat experience—and being equipped with U.S. weaponry—Israel lost more than 800 armored vehicles and 100 attack aircraft. Just six years after Israel stunned the world by quickly crushing a combined Arab army during the Six-Day War, the Yom Kippur War stood in stark contrast: It dragged on for weeks, required emergency U.S. assistance to backfill equipment losses, and Israel came uncomfortably close to defeat.
The Yom Kippur War was a wake-up call—and not just for Israel. Even though the United States was not a direct participant, U.S. Army leaders witnessed in real time how U.S. equipment and tactics used by the Israeli army fared against their Soviet counterparts in the Egyptian and Syrian militaries. The United States did not like what it saw. If U.S. forces did not adapt, Washington surmised, they might come similarly close to defeat—or worse—in a potential future conflict.
And so, the U.S. military went to work, studying every aspect of the war. Out of those lessons, the Army developed a new doctrine—AirLand Battle—as well as an updated training regimen that laid out a new blueprint for the post-Vietnam War, post-draft military. And while the United States never directly fought the Soviet Union during the Cold War, the Yom Kippur War—and the lessons the United States drew from it—provided the intellectual bedrock of how to blend ground maneuvers, precision air power, and overall speed: the very mix of strategies that enabled the United States’ lightning defeat of Soviet-equipped Iraq during the First Gulf War. Even half a century later, the Yom Kippur War continues to shape how the United States military thinks and plans for the future.
Today, Russia’s war against Ukraine could well provide as many insights about 21st-century warfare as the Yom Kippur War did for 20th-century conflicts. For decades, the U.S. Defense Department has shaped the U.S. military for flash conflicts and quick interventions where speed and precision rule. But one year into a war that some thought would last only days, Ukraine raises the question of whether the age of industrial warfare has returned. The consequence: The United States would need to prepare to fight a very different type of conflict than it plans for today.
A lot of ink has already been spilled questioning the continued relevance of the tank, for example, given the Ukrainians’ successful use of anti-tank weapons and ubiquitous small to large unmanned aerial systems in ground combat. The current war also raises questions about whether helicopters still have a place on the modern battlefield, given the 75 or so Russian helicopters, including scores of the most advanced models, that the Ukrainians have destroyed or damaged, mostly using relatively old air defense missiles.
And even though the Ukraine war is primarily a land war, the conflict has similarly raised disconcerting questions for the U.S. Navy. The sinking of the Russian cruiser Moskva—as well as the dozen or so other, smaller Russian vessels that have been damaged or destroyed by a country without any serious naval forces of its own—should raise serious questions about the survivability of large surface ships in modern war. Conversely, Ukraine’s success at employing smaller uncrewed vessels suggests a potential alternative way to wield naval power.
The lessons for the U.S. Air Force have been no less profound. Despite the prewar predictions that Russian airpower would quickly overwhelm Ukraine absent NATO’s establishment of a no-fly zone, Russia has failed to gain air dominance and the Ukrainian Air Force is still flying nearly one year into the war. The Ukraine conflict shows that airpower can, indeed, still operate within the range of enemy missiles—not with impunity, but not with certain death, either. Even more importantly, the war highlights the increasing importance of drones to modern combat in the land, sea, and air domains. Indeed, in some sense, manned aircraft have taken a backseat to remotely piloted aircraft in the battle for the skies over Ukraine.
Key lessons have emerged for space and cyberspace as well. The Ukraine war has been called the first commercial space war. Whether or not the label is accurate, there is no doubt that private space companies have played an outsized role in the conflict—from keeping Ukrainian forces online to providing the imagery that has shaped media coverage of the conflict around the world. In cyberspace, Russia’s vaunted capabilities never lived up to expectations, raising questions of whether cyberattacks really are the next weapons of mass destruction—as some have claimed—or whether their effects are somewhat more limited.
In sum, a year in, the Ukraine war is providing the same wealth of insights that the Yom Kippur War did a half-century ago. But there is one major difference that could turn into a problem: Whereas the Yom Kippur War painted such a vivid and bleak picture for the U.S. military that it was forced to innovate, the Ukraine war looks like a win for U.S. equipment and tactics—at least for now. As a result, the same impetus to heed the lessons and effect change is not there.
To its credit, the United States is doubling down on the capabilities that the Ukrainians have employed successfully. The Army, for example, is buying more artillery shells, more Javelin anti-tank and Stinger anti-aircraft missiles, and more High Mobility Artillery Rocket System launchers to make up for those expended in Ukraine. These, however, are arguably the easy lessons. They do not require the United States to do anything differently, only buy more of the same.
The United States is also right not to act on the non-lessons of the conflict. In some cases, the Ukraine war is simply not instructive. For example, Russia has kept its most advanced aircraft mostly over Russian airspace and out of range of Ukrainian air defense. The war, therefore, only offers inconclusive results so far on whether stealth aircraft or air defenses have the upper hand.
In other cases, the technological lessons may be clear, but the operational implications are not. Take the great tank debate, for instance. The battle for Kyiv showed that tanks are very vulnerable. At the same time, Ukraine’s successful counteroffensives in Kharkiv and Kherson oblasts demonstrated that there are few alternatives to armored warfare for taking ground, especially in open terrain. And so, it is perhaps unsurprising that the U.S. military is similarly split. The Marine Corps jettisoned its tanks, while the Army is pushing ahead with ever more modern ones.
The jury is still out, however, on whether the United States will embrace the hard lessons of the war—those that actually require the U.S. military to fundamentally change direction—especially if it requires learning from Russia’s failures, rather than Ukraine’s successes. The U.S. Army is still pressing ahead with its Future Vertical Lift program—the costly development of five new helicopter types—despite all the Russian helicopter losses. The Navy is still investing in surface ships, despite the sinking of the Moskva and other Russian vessels. And the Air Force remains committed to its manned aircraft fleet, despite the dominance of drones in the airspace.
Even more fundamentally, the United States needs to rethink the balance between capability and capacity. From missiles costing tens of millions of dollars each to planes costing hundreds of millions to ships costing billions, the U.S. military continues to default to the high end, even if it means acquiring fewer systems. But the Ukraine war’s most important lesson is that cheap and plentiful may, in fact, trump the exquisite but expensive. Indeed, Russia’s use of relatively small numbers of wonder weapons—such as hypersonic missiles—seemingly bought it little success. At the same time, the Ukraine war shows—just like the Yom Kippur War did—that numbers matter. Modern wars involve significant losses.
Indeed, for all the intense public debate on whether to give Patriot air defense systems, Abrams and Leopard tanks, or F-16 fighter jets to Ukraine, it currently appears that mass—more than any one particular weapons system—will determine the war’s outcome. While individual capabilities certainly help, as multiple commentators have noted, specific weapons systems are unlikely to meaningfully change the balance unless they are provided in sufficient quantities. In a protracted war, the question becomes less who has the silver bullet and more who simply has more bullets. And so, the United States needs to ensure that it, indeed, has more bullets.
To be fair, the Ukraine war is only one data point, and the U.S. military is not Russia’s. U.S. hardware may be more survivable and employed using more thoughtful tactics than the analogous Russian platforms. U.S. leadership may also be more circumspect and not fall victim to the same foibles as the Russians have in Ukraine. And U.S. strategy may, indeed, be better—raising the likelihood that the United States could win fast and not end up in a protracted conflict. (Although the Iraq and Afghanistan wars would suggest otherwise.)
Embracing the full implications of the war in Ukraine requires accepting the fact that there are still lessons to be learned from Russia’s failures. At the very least, the onus for future U.S. defense strategy must shift. Why won’t American helicopters, ships, or aircraft suffer the same fate as their Russian counterparts? Why won’t the next war turn into a protracted one? Why won’t the next war look more like the one in Ukraine?
Fortunately, major wars are rare events. And wars such as Russia’s in Ukraine—which provide a meaningful test of U.S. hardware and strategic assumptions without costing American blood—are even rarer occasions. But whether the war enables the United States to place wiser bets on the future as it prepares for the next conflict partly depends on the U.S. military’s ability to engage in introspection. And that, in turn, hinges on whether the United States allows itself to be blinded by Ukraine’s battlefield successes and potential victory.
If the United States does learn the lessons of this war, as it did after the Yom Kippur War 50 years ago, it may secure the U.S. military’s qualitative edge for decades to come. If it does not, it may not get a second chance.