China is watching one number in the Iran war more closely than any other

 The Missile Issue For The US If It Returns To A Full Bombing Campaign Against Iran: The US air campaign against Iran, Operation Epic Fury, was militarily very successful, severely degrading Iran’s ballistic missile stockpiles and missile launchers, while decapitating its senior leadership.

Decapitation strikes have eliminated over 40 senior military and political leaders, and US and Israeli air strikes have hit over 1,000 targets.

However, resuming a full-scale air war will rapidly drain U.S. missile and air-defense stockpiles. Following recent major air operations, military analysts confirm that the Pentagon is running dangerously low on precision-strike and long-range interceptor missiles, with industrial contractors needing years to replenish inventories to prewar levels.

During March and early April, and several weeks of unrelenting airstrikes, the US was facing a significant strain on its Tomahawk missile stockpile due to high usage in the recent operations against Iran, now and back last June, raising concerns about inventory levels for potential, larger-scale engagements.

President Trump insists that the “ceasefire” with Iran is still on, although the Iranians, as is the M.O., have ignored it repeatedly. After the shootdown of an Apache helicopter, the US responded with airstrikes on the Iranian coastline. Iran then sent missiles at US installations in the Middle East. Ceasefire?

What happens if (and it is a certainty if the US wants a deal worth anything) the air war is restarted? Can the US continue to conduct an air war with its missile inventory getting dangerously low?

Tomahawks, Patriots, THAADs In Short Supply

Also, the US used many of its Patriot and THAAD Interceptors, defending its bases in the Middle East and in Israel. Over $1.2 billion in air-defense assets were used at unprecedented rates, burning through up to 50 percent of the prewar inventory of critical systems.

The Washington Post claims that the US has fired 850 Tomahawks thus far during the airstrikes against Iranian targets. That is about a quarter of the entire missile supply, leaving the military with about 3,000 missiles to handle any further contingencies in Iran or, more importantly, against China should the need arise.

The US also used about 45 percent of its Precision Strike Missiles (PrSM) during the air campaign.

The Replenishment Rates For These Missiles Are Slow

While not completely exhausted, current replenishment rates are slow—often under 100-200 units annually—and struggling to keep pace with operational consumption, creating a long-term supply vulnerability.

“Manufacturers just can’t make them fast enough,” said Vertical Research Partners analyst Rob Stallard. “There was already way more [missile] demand than supply, and [Iran] exacerbates the issue.” How bad the acute pressure gets depends on how long the conflict lasts.

The US War Department has been talking with defense contractors about boosting production rates not just for Tomahawks but also for Patriot missiles, THAADs, and other weapons to ensure our warfighters stay equipped.

Estimates Show It May Take Years For The US To Replenish

Late last month, the Center for Strategic and International Studies (CSIS) released an analysis on military contractors and stated that it may take up to three years for the United States to replenish its missile stockpiles, just to get them back to where they were when the current conflict began.

"The United States has enough munitions for any plausible scenario in the Iran war, but the depleted inventories have created a window of vulnerability for a potential Western Pacific conflict," CSIS wrote. "The time needed to rebuild those inventories has thus become a major concern."

But the Pentagon realizes that the inventory must be built well beyond pre-Operation Epic Fury levels to conduct future operations, especially in the Indo-Pacific region.

Large munitions procurement in the Trump administration’s $1.5 trillion FY 2027 defense budget reflects the concerns with missile inventories.