American defense contractors will take upwards of three years to replace the primary munitions the U.S. military used during its 39-day bombing campaign against Iran, according to a new estimate from a D.C.-based think tank, emphasizing the concern from experts that the Iran war could impact a possible future conflict with China.

Secretary of War Pete Hegseth has said it could take “months and years … depending on the weapon system,” to refill U.S. stockpiles, though the department is trying to scale up the defense industrial base’s capacity to manufacture these munitions to exceed where they were at the start of the war.