(NEW YORK) — While President Donald Trump says Operation Epic Fury could last several weeks, a question some are raising is how long U.S. and allies’ missile defense stockpiles can last in an extended conflict with Iran.
Trump has insisted that the U.S. is well equipped to fight, with a “virtually unlimited supply,” and other Gulf states have pushed back on claims that they are running missiles.
How much of the U.S. interceptor stockpile is being used up to defend against Iran’s continued heavy missile and drone attacks is classified, but it’s expected to be among questions lawmakers have for top Trump administration officials this week when they brief lawmakers on Capitol Hill.
Some experts are also raising concerns about America’s cache of the expensive air defense missiles as the Iranian military continues to target U.S. assets and other allies in retaliation.
Kelly Grieco, a senior fellow at the Stimson Center think tank and former assistant professor at the Air Command and Staff College, told ABC News that the conflict is becoming a “war of attrition.”
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The U.S. and Israeli militaries are now in a race to destroy Iran’s missile capabilities, including launchers and production facilities, before the U.S. and Israel’s own stockpile of air defense interceptor missiles in the region is depleted, according to Grieco.
“The question is becoming who runs out of missiles first. Does the defender run out of interceptors,” she asked, referring to the armies of the U.S., Israel and the Gulf states. “Or does Iran run out of missiles, or their ability to launch missiles?”
“If the Iranians are able to launch with the kinds of numbers they have been launching over the past 48 hours over the next four to five weeks, that does not seem sustainable from an interceptor perspective,” she added.
“But if those numbers drop off because the U.S. and Israel destroy the launchers themselves, or their storage facilities, and the numbers drop dramatically, then we could potentially sustain this campaign,” Greico said.
Retired Lt. Gen. Dan Karbler, former commander of the U.S. Space and Missile Defense Command, told ABC News Live Tuesday that extensive drone use by the Iranian military has prompted the use of smaller short-range missiles as interceptors.
“We don’t want to shoot Patriot missiles at the drones,” he said. “So, some of our short-range air defense, more capability of that type of nature needs to flow into countries so we’re using our short-range missiles to take out these drones not our very limited patriot missiles.”
President Trump attempted to assuage concerns about the stockpile Tuesday — but also acknowledged the number of some of the highest-grade munitions is “not where we want it to be.”
“The United States Munitions Stockpiles have, at the medium and upper medium grade, never been higher or better — As was stated to me today, we have a virtually unlimited supply of these weapons,” Trump wrote on social media early Tuesday morning.
And even as he says the U.S. will “easily prevail” in this war and that the U.S. is prepared for the operation to go on for “whatever it takes,” Trump wrote that “Wars can be fought “forever,” and very successfully, using just these supplies.”
The U.S. was already concerned about its stockpile before this war as the Russian-Ukraine conflict, the Israeli-Gaza conflict and last summer’s conflict with Iran have dramatically increased demand for Patriot and THAAD missiles, according to Greico.
Terminal High Altitude Area Defense missiles that are used to defend against Iran’s most powerful ballistic missiles are in particularly short supply. Grieco estimated that if the U.S. uses its THAAD missiles at same rate as the 12-day conflict with Iran last year, it likely only has enough for about two weeks now at most.
Grieco said it will take a long time, and be costly, for the U.S. and other countries to replenish their antimissile stockpiles, which are more time consuming and expensive to produce than the Iranian weapons they defend against.
Iran has not launched missiles at the same scale so far compared to the attacks during conflict with Israel last year.
Israeli officials and independent experts said they believe that may reflect a strategy by Iran to run down air defense supplies with relatively smaller but steady attacks over a longer period.
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