Recent U.S. and Israeli operations against Iran and the latter’s retaliatory strikes have once again demonstrated the mathematics of modern air defense. Waves of Iranian-designed Shahed-136 drones—crude, slow, and estimated to cost as little as $20,000 apiece—have in a number of exchanges forced the United States and several Gulf partners to expend Patriot and SM-6 interceptors that cost millions of dollars each.

Interception rates have been impressive. A successful shoot-down that requires a high-end interceptor, however, can be a Pyrrhic victory. The defender burns through scarce and expensive munitions while the attacker draws from comparatively large stockpiles of low-cost systems. This is the drone attrition trap. And it is not new.

Recent U.S. and Israeli operations against Iran and the latter’s retaliatory strikes have once again demonstrated the mathematics of modern air defense. Waves of Iranian-designed Shahed-136 drones—crude, slow, and estimated to cost as little as $20,000 apiece—have in a number of exchanges forced the United States and several Gulf partners to expend Patriot and SM-6 interceptors that cost millions of dollars each.

Interception rates have been impressive. A successful shoot-down that requires a high-end interceptor, however, can be a Pyrrhic victory. The defender burns through scarce and expensive munitions while the attacker draws from comparatively large stockpiles of low-cost systems. This is the drone attrition trap. And it is not new.

Ukraine has been living inside it for four years, absorbing tens of thousands of Iranian-designed drones that have been manufactured by Russia. What is new—and strategically alarming—is that the United States now faces similar pressures, though not yet remotely on the same scale, without fully institutionalizing the lessons that Ukraine has learned under fire. The main lesson is simple: You cannot solve a cheap problem with expensive solutions and expect to remain solvent.

The asymmetry begins with industrial scale. Iran has spent decades developing a drone ecosystem through state-owned firms, research programs, and distributed manufacturing. Conservative estimates place annual Shahed-family output in the tens of thousands. Even at the lower end of those estimates, the scale is sufficient to challenge missile-based interception as a sustainable defense model.

Ukraine’s experience demonstrates how rapidly this dynamic can evolve. Ukrainian drone producers told us during a recent visit........

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