American Power Is Dangerously Overstretched by Trump’s Iran War

The war has featured impressive tactical feats by the United States and Israel, such as the killing of dozens of high-ranking Iranian officials in the opening hours of the fight. The capabilities on display over Tehran—and U.S. President Donald Trump’s penchant for military risk-taking—have surely been sobering for Washington’s adversaries in Moscow and Beijing. Yet the war has had more ambiguous, sometimes damaging, strategic outcomes. It has also caused an alarming depletion of key U.S. weapons stockpiles while ripping capabilities away from other dangerous theaters. In short, the conflict has badly strained a military that has been trying to do too much with too little for far too long.

There’s a saying in the Defense Department that every U.S. war plan is an existential threat to all the other war plans. A draining conflict in the Middle East may make it harder for Washington to deter a far more devastating fight in the Western Pacific—and usher in a dangerous period in which an overtaxed U.S. military struggles to respond to surging global risks.

Danger doesn’t have to bring disaster: It’s possible that the United States will navigate the coming years without a catastrophic failure of deterrence. Crises can have silver linings: If this crisis catalyzes greater, sustained urgency in closing the gap between the Pentagon’s sprawling commitments and its all-too-finite capabilities, it may have a salutary strategic effect. But the period immediately ahead looks menacing. The world is getting more violent and more disordered—just as Trump’s war has made Washington’s chronic overstretch more acute.

The USS Gerald R. Ford arrives at Souda Bay naval base on the Greek island of Crete on March 23, after taking part in Middle East war operations. Costas Metaxakis/AFP via Getty Images

Over the past two decades, the global threat environment has gotten uglier and more crowded. A country that once towered over adversaries now faces challenges from revisionist great powers, angry rogue states, and tenacious nonstate foes. Looming above all other dangers is a new cold war—with the risk of a catastrophic hot war—against a relentlessly arming China. Yet the United States has sought to handle what increasingly looks like a perilous prewar situation with a post-Cold War approach to military spending. U.S. defense budgets, typically between 3 and 4 percent of GDP, have remained low by historical standards. Fatigue from long wars in Iraq and Afghanistan after 9/11 made the politics of defense more difficult. The predictable result has been a growing mismatch between Washington’s global commitments and its military resources—a mismatch that one nonpartisan expert commission after another has identified and that one administration after another has tried and failed to fix.

The seemingly perpetual pattern is one in which each new administration promises to better apportion scarce resources through stricter prioritization—only to end up intervening in precisely those places it aimed to avoid. Barack Obama promised a pivot to the Pacific but ended up mired back in the Middle East. The first Trump administration touted the return of great-power rivalry but was then consumed by crises with North Korea and Iran. Joe Biden sought to stabilize relations with Moscow and Tehran so that the Pentagon could finally gear up for China. But then Russia launched a full-scale invasion of Ukraine in 2022, and the Middle East exploded a year later. The desire for focus and the divestment of lesser problems has consistently collided with the realities of a messy world in which Washington still has global interests. Trump’s second term was supposed to fix this problem but made it much worse.

Trump initially filled the Pentagon with “prioritizers” who wanted to emphasize Asia and “restrainers” who wanted out of the Middle East. His administration pushed European and East Asian allies to take greater responsibility for their own defense. His new National Security Strategy and National Defense Strategy proclaimed that the era of costly Middle Eastern wars was over. Trump 2.0 promised discipline after decades of distraction. Instead, it brought omnidirectional, almost hyperactive, intervention.

To wage a short but fierce war against the Houthis in early 2025, Trump surged aircraft carriers, precision-strike capabilities, and other assets into the Middle East. He then struck Iran while sending precious air and missile defense capabilities to protect Israel during the countries’ 12-day war in June. The administration carried out counterterrorism operations in Nigeria, Somalia, and elsewhere, including one of the largest bombing raids in the history of the U.S. Navy. In December 2025 and January 2026, U.S. forces blockaded Venezuela and smashed their way into Caracas to seize President Nicolás Maduro. Washington continued to provide scarce weapons, including Patriot missile interceptors, to Ukraine.

Each of these initiatives served a compelling U.S. interest, including defending freedom of navigation, rolling back Iran’s nuclear program, and reasserting the Monroe Doctrine. Some of them, such as the bombing raid on Iran’s nuclear facilities in June 2025 and the snatching of Maduro, were strikingly successful. But each of these interventions increased the strain on an overextended military. The corrosive effects were becoming obvious even as this year’s Iran crisis began.

Trump was initially inclined to strike in January, after the Iranian regime defied his warnings by massacring thousands of protesters. But he couldn’t start the war then because the necessary resources were nowhere near the Middle East. Strike aircraft, air and missile defense, and other capabilities had to be assembled from distant regions. The USS Gerald R. Ford aircraft carrier, for example, had been pulled from the Mediterranean to the Caribbean to support operations in Venezuela—and now had to race back to the Middle East. The U.S. military was out of position for a crisis because limited capabilities were being stretched across a seemingly endless set of missions. The course of the subsequent war revealed both the lethal proficiency and perilous inadequacy of U.S. arms.

In addition, the United States and Israel dramatically accelerated the process of finding and striking targets with the help of artificial intelligence. One of the most intense, concentrated air campaigns in modern history saw the use of nearly 5,200 munitions in just the first 96 hours. Michael Brown, a former director of the Pentagon’s Defense Innovation Unit, called the conflict the “first AI war”—the first time a global superpower used AI-enabled capabilities at scale in sustained, high-intensity combat. The war advertised an unmatched ability to fuse precision strikes with pinpoint intelligence. In the force-on-force contest, the United States and Israel savaged an enemy armed, in part, with Russian and Chinese weapons.

This performance, however, didn’t demolish a resilient Iranian regime. It didn’t prevent Iran from using drones and missiles to strike U.S. bases in the region and inflict painful punishment on other Gulf countries. It also did not keep Tehran from putting a hammerlock on the Strait of Hormuz. As of this writing, the war’s strategic results were notably ambiguous: Iran was pummeled and empowered all at once.

In a U.S. Navy handout, sailors prepare to stage ordnance on the flight deck of the USS Abraham Lincoln in support of Operation Epic Fury on Feb. 28. U.S. Navy via Getty Images

The size of most critical U.S. military stockpiles is classified, and the Defense Department hasn’t said precisely how many munitions were used. But according to published estimates by the Center for Strategic and International Studies, based on publicly available data, U.S. forces fired more than 1,000 long-range Tomahawk cruise missiles, or roughly one-third of the entire stockpile, during the phase of intense fighting from late February until early April. That phase also consumed roughly one-quarter of the military’s JASSM stockpile (another long-range cruise missile), along with smaller shares of other standoff munitions that allow U.S. forces to deliver destruction from a distance. Similarly, shielding U.S. forces and regional partners from Iranian drone and missile salvos required large numbers of high-end weapons that are mainstays of U.S. air and missile defense—for example, somewhere between 30 and 60 percent of the Pentagon’s SM-3 ballistic missile interceptors, the majority of its THAAD missiles, and around half of its Patriots.

These systems are central to U.S. contingency plans in multiple theaters, and there aren’t nearly enough to go around. Tomahawk and JASSM missiles and THAAD, Patriot, and SM-3 interceptors would be at the heart of U.S. contingency plans in the Western Pacific, whether to strike Chinese targets from a safer distance or to protect bases and allies from Chinese strikes. These weapons were already in short supply before this war: Think tank studies and wargames have repeatedly shown that U.S. forces don’t have the magazine depth for a protracted great-power fight. Replenishment could be a lengthy process. At current production rates, it could take up to four years just to replace the weapons used against Iran.

That’s not the only way this war required robbing the future to pay the present—or robbing other regions to fortify the Middle East. The saga of the Gerald R. Ford, whose exhausting back-to-back-to-back deployments in the Mediterranean, the Caribbean, and once more in the Middle East constituted the longest stretch at sea for an aircraft carrier since the Cold War, is instructive. It’s part of a larger pattern of heavy naval deployments in the Middle East since Hamas’s Oct. 7, 2023, attack on Israel, which have run the U.S. surface fleet ragged and may limit the availability of key assets in the future. The Pentagon stripped East Asia of key resources—including THAAD missiles and marine amphibious units—not long after issuing a National Defense Strategy that called that region the priority theater for the United States. More broadly, any war of such intensity stresses innumerable elements of the force—aircraft, ships, submarines, and personnel—that perform an array of vital missions. The stress may persist for some time to come.

The initial phase of the war lasted six weeks, from late February to early April. Yet it was followed by a resource-intensive U.S. naval blockade and preparations for a potential renewal of the fighting. At one point, there were three U.S. carrier strike groups in the Middle East, roughly the number that are typically deployed globally at any given time. Even in a relatively optimistic scenario, it seems likely that the United States will be engaged in long-term containment of a wounded but vengeful Iran, akin to the containment of Saddam Hussein’s Iraq after the 1991 Gulf War. That mission will continue to demand significant U.S. resources—and create gaping vulnerabilities for a superpower that was already overstretched.

Sara Gironi Carnevale illustration for Foreign Policy

For decades, a determined Chinese buildup has been changing the strategic landscape of the region, by making it more difficult for Taiwan to resist an assault—and harder for the United States to come to its aid. More recently, Beijing has embarked on rapid-fire expansion of its nuclear arsenal, which could provide coercive leverage in a crisis. Indeed, Chinese President Xi Jinping is putting the pedal to the metal: People’s Liberation Army watcher Sam Roggeveen called 2025 a “red banner year” as the Chinese military rolled out many new programs and capabilities, from additional aircraft carriers to sixth-generation fighters.

Xi has instructed his generals to be ready for a Taiwan operation as early as 2027. An invasion isn’t the only option, of course: The Chinese military regularly conducts exercises—U.S. officials call them “rehearsals”—for a no-notice quarantine or blockade meant to strangle Taiwan into submission. Beijing’s gray-zone coercion of Taiwan and other East Asian neighbors is only getting bolder over time. The danger, then, is that continuing conflict in the Gulf will deplete and distract the U.S. military just as China is becoming stronger and more assertive.

This problem isn’t entirely new: In 2022, Michael Beckley and I warned that the United States would enter a “danger zone” in the late 2020s. At that point, China’s military buildup would be maturing, while U.S. power temporarily dipped as the Pentagon retired older ships, planes, and submarines—and newer U.S. and allied investments would only gradually change the balance for the better. With the Iran war reducing U.S. stockpiles to even more glaring levels of insufficiency—and considering the many years it may take to replenish them—that danger zone could get longer and more severe.

It’s important not to overstate this point—or ignore the possibility that the war could have positive impacts on global perceptions of U.S. strength. The Pentagon’s performance against Iran might bolster deterrence by dramatizing the qualitative superiority of the U.S. military, as well as Trump’s willingness to lash out against hostile states that earn his wrath. The war has also demonstrated how damaging drones and missiles can be to ill-defended surface ships—a problem for Xi if he sends an armada of troop and equipment transports across the Taiwan Strait. Trump’s counterblockade of Hormuz made real one of the great Chinese strategic anxieties of the last few decades by showing how readily the U.S. Navy could choke off China’s oil imports in a crisis. Deterrence is a psychological phenomenon, and aspects of the recent crisis surely give Xi pause about launching a military adventure of his own.

Also bear in mind that Washington isn’t the only great power with readiness problems. Xi’s serial purges have effectively lobotomized the top ranks of the Chinese military. “We’re running out of munitions, but they’re running out of generals,” one well-informed U.S. observer told me. And don’t make the mistake of thinking that Xi’s decision to attack would simply be a matter of missile arithmetic. Such an epic, legacy-defining decision would surely flow from a more complex assessment of costs and risks.

Yet none of this can be particularly comforting to China hawks in the Trump administration who spent the Biden years scoffing at the idea that looking strong while spending down key assets in Ukraine or the Middle East would strengthen the U.S. hand in the Western Pacific. Even if conflict with Iran could fortify the psychological pillars of U.S. deterrence, it has weakened the material foundations of that deterrence. And whatever the complexity of Xi’s calculations, U.S. military weakness creates greater risk that China could choose to test the status quo more aggressively—or that deterrence could fail if an unanticipated crisis sends tensions soaring and brings the cross-strait standoff to a head.

If a war does occur in the Western Pacific, a degraded and globally scattered U.S. military would face higher chances of grievous losses, an indecisive outcome, or an outright defeat. Remember: Concerns about the U.S. military simply not having enough to prosecute a protracted fight with China were rising well before Trump’s latest battle with Iran. Even short of that horrific eventuality, acute overstretch could incur serious strategic costs.

In a U.S. Air Force handout, a crew chief guides in a F-35A Lightning II following a large-scale strike against Venezuelan military targets in Ceiba, Puerto Rico, on Jan. 3. Katelynn Jackson/U.S. Air Force via Getty Images

Some of these dynamics are already discernible. Chinese propagandists have pointed to a decrease in U.S. patrol flights in the South China Sea as evidence that Washington is forever mired in the Middle East. Regarding U.S. force repositioning, one Chinese expert noted that “any weakening of its presence in the Asia-Pacific will inevitably work to someone’s advantage—and you can imagine who that is.”

Former Japanese Defense Minister Gen Nakatani has warned that the recent removal of U.S. marine units and other capabilities from the Western Pacific could “destabilize the balance of power around Japan.” The United States also removed THAAD interceptors from South Korea, even though Seoul had paid a heavy price for the original deployment of those interceptors in the form of economic punishment imposed by Beijing. South Korean President Lee Jae-myung said in March that the war compels greater self-reliance because “you always have to think about what you’re going to do if there’s no external support.” But self-reliance could also get harder because the war is delaying U.S. arms sales to allies: In April, reports emerged that U.S. officials had notified Japan that delivery of some 400 Tomahawk missiles would be postponed.

To be sure, day-to-day military cooperation in most of Washington’s Pacific alliances is excellent. No one thinks the United States is leaving the region anytime soon. But another costly intervention in the Middle East is producing fears that Washington has once again failed to pivot its attention and resources to the Pacific—just as the military peril is becoming more acute.

Beyond alliance challenges in East Asia, there will be other global ramifications. Ukraine will be a winner of this war, in the sense that the world now realizes it desperately needs the cost-effective drone defenses that Kyiv makes at scale. But it will also be a loser, in the sense that the war has made it harder for Washington to sell its European allies key weapons, above all missile defense interceptors, for provision to Ukraine. More broadly, the war raises the odds of a repeat of Washington’s problem in January. The situation in which the Pentagon found itself as the Iran crisis unfolded—fatigued, out of position, unable to respond promptly—may become more the rule than the exception in the years ahead.

Overstretch brings heightened risk of catastrophes such as deterrence failure and military defeat, along with everyday costs such as strained alliances and loss of diplomatic leverage. A superpower that became accustomed to outright military supremacy in the post-Cold War era will now have to grapple with the dilemmas its weakened position brings.

The United States faced an earlier danger zone in the late 1940s and early 1950s, when the Soviet acquisition of nuclear weapons and then the Korean War revealed how tenuous the Pentagon’s global position was. That crisis spurred a massive military buildup that bolstered an emerging U.S. alliance network and gave the free world tremendous leverage and strength. During the 1970s, a relentless Soviet buildup threatened to tilt the balance back in Moscow’s favor—until the United States and its allies responded, after the Soviet invasion of Afghanistan in 1979, with a multiyear program of military enhancements that helped the West win the Cold War. These crises were useful catalysts. Could Washington’s current military insolvency have a similarly invigorating effect?

There are some encouraging signs. The Trump administration has proposed historic increases in the defense budget, which would raise military spending to between 4 and 5 percent of GDP. It is seeking to dramatically accelerate the production of crucial weapons, including many of those used so heavily against Iran. Precisely because the war has elicited such deep concerns about U.S. presence and power, it will probably give Washington’s allies in Europe and the Pacific even greater incentive to augment their own strengths. It could impel creative efforts to forge a more integrated defense industrial base among the democracies, in which key U.S. allies help produce capabilities, such as Patriot or SM-3 missiles (a variant of the latter is already a joint Raytheon-Mitsubishi effort), or ease the U.S. shipbuilding crisis by constructing vessels for the U.S. Navy in their own yards.

Not least, the Iran conflict has revealed how emerging technologies, above all AI, can be a force multiplier for Washington and its allies—and served as proof of concept for potential uses in other theaters. The war should drive investment in smaller, less exquisite capabilities—such as one-way attack drones—that can deliver firepower in ferocious volumes, as well as in tools that can defeat incoming drone attacks without devouring scarce, expensive air defenses. So much of the fallout from the Iran war depends on what the United States and its allies do next. Perhaps now will be the moment when Washington recognizes and comes to grips with the dangers that its long-accumulating, now acute overstretch can bring.

Or perhaps not. The United States mostly squandered a prior crisis—the Russia-Ukraine war—that showcased the debility of its defense industrial base and the limits of its stockpiles. That industrial base is shot through with fragilities and chokepoints that make it hard to radically and quickly expand production, even if the money is there. It’s still not clear that the money will be there over the medium and long term: Washington’s frail fiscal position makes sustaining high defense spending politically and economically arduous. And a problem that develops over decades can’t be solved overnight: Even if the United States summoned all the urgency and resources needed to return to strategic health, it could be years before some capabilities materialize in numbers that meaningfully affect the balance.

One way or another, the result of another draining war in the Middle East is likely to be a period of greater U.S. strategic vulnerability. The choices Washington and its allies make now will determine how long, and perhaps how deadly, that moment of peril will be.