The United States could probably take Kharg Island relatively quickly. But holding it would be much more difficult and could turn deadly. Iran might order its forces to set the oil facilities there on fire, much as Saddam Hussein did with Kuwait’s oil fields in the Gulf War, contaminating the area and sickening U.S. troops. On the small island of Kharg, U.S. forces would have less access to the equipment they would need to deal with this problem than their predecessors did in Kuwait, and they couldn’t easily move away or upwind from the fires.

But even without such tactics, the Iranians could make holding Kharg very difficult. The operation would likely take longer than 15 days, which is about how long an expeditionary unit can operate without logistical support. Kharg is far—140 miles—from American assets in Kuwait City, but very close to Iran’s coast. Resupply vessels would be exposed not only to cruise-missile fire but also to Iran’s “mosquito fleet,” which includes robotic drones, sometimes called unmanned surface vessels (Ukraine used similar devices to bottle up the Russian Black Sea fleet at Novorossiysk).

The final threat is one suggested by experiences in Ukraine. Russia has been using loitering munitions—drones that hover over a territory, scanning for targets that they then dive in to destroy—to great effect. Called Lancets, these cost about as little as Shahed drones, and Iran could employ them over Kharg to seek out resupply ships and aircraft in the process of loading or unloading, as well as vehicles and troops. To guard against loitering munitions has required Ukraine to cover entire road systems with nets. In April 2024, Iran unveiled its own version of the Lancet. This could be a fake meant to boost domestic morale—Iran has done that sort of thing in the past—but if it’s real, it could cause real problems.

U.S. troops may well take Kharg Island, only to endure ballistic-missile strikes, drone attacks, and petrochemical smoke, all without a reliable means of obtaining logistical support. The result could be a grinding war of attrition that more closely resembles the battle space in Ukraine than it does the “shock and awe”–style campaigns that Americans are used to. Iran has given every indication that it would likely escalate by striking oil-and-gas facilities in the region, just as it did to Qatar and Saudi Arabia after the Pars South gas field was struck. Ground casualties and the destruction of oil infrastructure throughout the region would almost certainly create pressure on Donald Trump to pull out; but extracting troops under loitering munitions is dangerous, and aircraft on the ground are prime targets for these circling drones.