As the US restarts war on Iran, is its weapons stockpile running low?

What Happened

The United States restarted large-scale attacks on Iran last week, following a ceasefire that had been in place since April and a memorandum of understanding signed in June. The US Central Command launched heavy waves of attacks on Iran's military sites, continuing for four nights since Sunday, targeting railway tracks and bridges. President Donald Trump threatened in a Fox News interview to 'knock out all their power plants... all their bridges' unless Iran negotiates, a violation of international law. The escalation came after Iran fired on three commercial ships in the Strait of Hormuz for using an unapproved route. The US has reinstated a naval blockade on Iran-linked ships and reimposed sanctions. Iran's Islamic Revolutionary Guard Corps (IRGC) retaliated with attacks on US military assets in Bahrain, Oman, Qatar, and Kuwait. Analysis by the Center for Strategic and International Studies (CSIS) indicates the US has expended more than half of its stockpiles of at least four critical munitions—Tomahawk missiles, JASSMs, PrSMs, and SM-3s—since the war began on February 28. CSIS estimated that over 1,000 Tomahawks, 1,100 JASSMs, 40–70 PrSMs, and 130–250 SM-3s were used, racking up billions in expenses and leaving low inventories that could take months to years to replenish.

Key Actors

Why It Matters

The rapid expenditure of high-end munitions weakens the US military's ability to sustain a prolonged campaign against Iran and degrades readiness for a potential conflict with China, a core strategic concern. The renewed violence destabilises the Persian Gulf, threatens commercial shipping, and risks a wider regional war. Trump's explicit threat to strike civilian infrastructure signals a possible erosion of adherence to international humanitarian law, which could draw international condemnation and further isolate the US diplomatically.

Watch For

President Trump's scheduled address at the US Army War College summit in Carlisle, Pennsylvania, on Wednesday, where he may announce further military or diplomatic steps. Continued US strikes and IRGC retaliations, especially on US bases in Bahrain, Oman, Qatar, and Kuwait. CSIS and other analysts' follow-up reports on stockpile levels and production timelines. Potential diplomatic efforts, including any backchannel negotiations following Trump's statement that American negotiators could continue talks. Monitoring of the Strait of Hormuz for shipping disruptions and Iran's enforcement of its approved routing.