When the United States began bombing Iran, it expected to quickly overwhelm the country’s government. In the war’s first 24 hours, American and Israeli forces hit roughly 1,000 targets. Over the following 37 days, they blew up 12,000 more, laying waste to much of Iran’s military infrastructure. The strikes killed Iranian Supreme Leader Ali Khamenei, Iran’s minister of defense, and the head of the Islamic Revolutionary Guard Corps.
But more than six months later, the Iranian regime not only remains intact; it is perhaps stronger than before. It immediately replaced lost officials and struck back at Washington and its regional partners. And it shuttered the Strait of Hormuz, driving up energy prices around the world and winning newfound political leverage—all to the great frustration of U.S. officials.
There are several reasons why Iran performed surprisingly well. For one, the country had long planned for American and Israeli attacks, so it was prepared to reconstitute its government when top leaders were killed. It was also able to import enough goods to keep its economy from completely collapsing despite a U.S. naval blockade. But one of the most significant factors is that the Islamic Republic had built up a large arsenal of cheap yet accurate drones and missiles. These munitions made Iran’s counterattacks effective and allowed it to close the strait—and thus deter American escalation.
In doing so, Iran has demonstrated something broader. The age of what I called precise mass—or high-volume, low-cost, precision-guided weapons—is well underway. It is no longer possible for the U.S. military, or any military, to win a full-blown war simply by using small numbers of exquisite weapons to dazzle opponents. Weaker countries can match stronger ones through offensive barrages. Offense is currently cheaper than defense: the price of effective interceptors has yet to fall to the level of attack drones and missiles, which means defending against precise mass is extremely costly. After all, militaries cannot endlessly block salvos of $35,000 Shahed-136 attack drones with $4 million Patriot missiles.
To be sure, the war in Iran also shows that advanced technology remains essential. The United States, for example, had great success hitting valuable Iranian sites because it has artificial intelligence systems that can identify and recommend targets faster than ever before. American exquisite weapons are still much harder to stop than cheaper ones, and they are more likely to destroy targets in a single strike. But the world is learning from Iran, building on what Ukraine had already made clear: the future of war lies in part in precise mass. Everyone will now embrace the imperative of producing and using hosts of cheap and disposable weapons systems, changing warfare and the military balance.
SET IN ONE’S WAYS
In war, it might seem as if wealthy states always benefit from new military capabilities. But the reality is more complicated. If a new system is expensive, it indeed favors rich incumbents. But if it is cheap and demands large organizational changes to adopt, other countries can take advantage just as quickly—if not faster. In fact, the most powerful militaries in the world often struggle in the face of required disruptive organizational change, as their prior success has created bureaucracies and organizational biases that make adaption harder. As a result, they have a hard time integrating new capabilities that cannot be plugged into their existing structures.
Precise mass is just such a capability. The most conventionally powerful militaries are organized around small numbers of exquisite, expensive, hard-to-produce weapons and platforms such as Tomahawk missiles and F-35s. Their units train and plan around these systems. They thus cannot easily adjust to precise mass capabilities, which require different kinds of training and entirely new conceptions of how to fight. Exquisite systems, for instance, are scarce, so units must take great care not to waste systems and to minimize the risk of destruction. With precise mass, by contrast, units are supposed to move quickly and not make the perfect the enemy of the good. This helps explain why the United States has struggled to adapt to precise mass—even though the country invented precision guidance and boasts the best military in the world.
Iran, meanwhile, has been broadly locked out of some more advanced military capabilities. As a result, it had to invest heavily in long-range, one-way attack systems and cheap ballistic missiles. The result is a war where Iran has dramatically outperformed expectations. Tehran could not go blow-for-blow with the U.S. military’s exquisite weapons, but it did not need to, because it could rapidly fire relatively accurate drones and cheap missiles at U.S. bases and the region’s critical infrastructure. The United States has dealt billions of dollars of damage to Iran in turn, but only by burning through its stockpiles of Tomahawks, SM-6 missiles, and other expensive systems. As a result, Washington now has to sprint to resupply its own stocks and those of partners elsewhere, such as Taiwan and Ukraine.
Weaker states are no longer priced out of the military power game.
Thanks to rigorous preparations, meanwhile, Tehran has been able to withstand the intensive damage. In the years before the war, Iran built a vast underground network of missile infrastructure spread across its territory that has proved impossible for U.S. and Israeli forces to eliminate thus far. The United States had even more trouble destroying Iran’s heavily dispersed missile production facilities, inverting assumptions that have guided American airpower campaigns since Operation Desert Storm against Iraq in 1991, where the emphasis was destroying existing weapons stockpiles.
Iran has shown that weaker states are no longer priced out of the military power game, and the United States has discovered that stronger states are not guaranteed the upper hand in major battles. Little wonder, then, that countries rich and poor are investing in precise mass. North Korea, for example, has received Iran’s Shahed technology and production equipment from Russia and is using it to develop its own cheap uncrewed vehicles. A company in Nigeria has contracted with a Turkish manufacturer to build 100,000 one-way attack drones at local assembly facilities. Poland has increased spending on drones and counterdrone systems from about $27 million in late 2023 to roughly $6.9 billion this year and established domestic drone factories. Six European states, including France, Germany, and the United Kingdom, signed a letter of intent to jointly develop a one-way attack drone with a range of over 300 miles and a target cost of less than $100,000. Saudi Arabia has unveiled its own attack drone modeled on the Shahed with a supposed range of more than 900 miles. And Japan’s governing party has requested a record $55.6 billion defense budget, largely so that it can buy great quantities of attack drones.
OFFENSE OVER DEFENSE
The Iran war shows that nearly every military can acquire lots of precision strike weapons that cost tens of thousands of dollars apiece. But defense remains much more expensive. There are very few reliable interceptors that cost less than $1 million. To repel Iran’s precise mass, Washington had to use about 65 percent of its Patriot interceptors and 35 percent of its THAAD interceptors, leaving it with roughly 1,000 and 250 of each type, respectively. The country’s partners in the Middle East are also running out of air defenses.
For the United States, this challenge was inevitable. The exclusive focus on exquisite systems since the end of the Cold War extended to how it approached defense, emphasizing antimissile systems intended to stop high-end ballistic and cruise missile attacks. Meanwhile, policymakers assumed that wars would be short, so they did not focus on designing defenses that could be easily scaled.
Now, Washington and other governments are trying to come up with cheaper defensive systems, experimenting with technologies such as directed energy weapons and high-power microwave systems that could destroy incoming drones. They are looking at interceptor systems that simply need to get near drones and explode to destroy them, rather than actually make contact head on. The international market has started to move: Ukraine is fielding interceptor drones that cost just $1,400 apiece, and European and Gulf-based startups are likewise building cheaper interceptors. But none of these systems appears ready to scale now.
The Iran war has also highlighted American capabilities that should prove useful in the new era of warfare. Over the last few years, AI that aggregates intelligence from many sources and cues up targeting recommendations for commanders has become an essential part of conflict, giving the United States—with its many AI companies and experience building so-called decision-support platforms—an advantage. Washington, for example, fielded the Maven Smart System, allowing it to dramatically increase the rate of its military strikes. This system has not been flawless; it may, for example, have mistakenly flagged an Iranian school as a target due to faulty intelligence inputs it was not enabled to check, contributing to a strike that killed over 100 children. The incredible speed of targeting selection also increases the risk of automation bias, whereby humans will outsource cognition to imperfect algorithms, leading to errors. But the system has apparently made targeting relatively more accurate, and the U.S. military can implement reforms that would make targeting mistakes even less likely. That means the binding constraint on how quickly a U.S. campaign could move is no longer intelligence processing, but inventory.
Critically, however, Washington’s AI gains came from better data architecture and the organizational integration of models mostly unveiled in 2025 or earlier, not the latest frontier ones. That means the current race to artificial general intelligence is not the principal driver of how AI is shaping warfare. In fact, as cheap open-source models inevitably gain the same capabilities as the ones Washington is using today, other militaries will find it easier to use AI to build similar decision-support tools. That may include Iran’s, which according to the AI company Anthropic tried to use its large language model Claude to target U.S. forces in the region.
CHEAP SHOTS
The U.S.-Israeli war on Iran shows that the age of precise mass is here. Tehran has demonstrated how less powerful countries can stymie more powerful ones in the modern battlefield. More powerful countries will also embrace offensive strategies that depend on precise mass, since the cost of defending against cheap munitions remains much greater than the cost of attacking with them.
As the world learns this lesson, the United States must as well. The country’s reliance on exquisite, expensive, hard-to-produce weapons is no longer enough to win wars and protect allies, especially given that the United States is drawing down missile stockpiles needed to deter China and others. Ideally, Washington would start scaling precise mass, investing heavily in low-cost defenses, and, crucially, adapting its organizational structures to use these tools effectively. American defense officials—accustomed to fighting only with exquisite systems—may struggle to accept this needed shift, especially if the defense budget shrinks, which could easily lead Washington to prioritize older and proven legacy capabilities, no matter their limits. And even if the Pentagon starts making changes, the country will require talented military commanders and senior civilian defense officials to stay in power long enough to drive these innovations through. Right now, the Pentagon is rapidly churning through both types of leaders.
Americans should hope that Washington will find a way forward. New innovations have, at least for now, closed the military gap between rich states and poor ones when it comes to offensive capacities. If the United States wants to maintain its military edge, it has no choice but to embrace precise mass—and stop carrying on as if the Cold War just ended.
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