Iran has increasingly tested US air defences across the Middle East, using waves of drones and missiles to overwhelm American systems and force the US military to use up valuable Patriot interceptors. During five intense days last month, Iranian forces attacked three US bases in Jordan.

On the fifth day, 17 July, a missile struck prefabricated housing units at one of the bases, killing three US soldiers and injuring more than 100 others.

Pentagon officials later acknowledged that scores of additional troops were injured and several aircraft were damaged during the attacks. “We shot down almost all the missiles,” Secretary of State Marco Rubio said when asked about the fatal strike. “One leaked through.”

The attacks have highlighted two growing challenges for the US military: Iran’s increasingly sophisticated ability to evade air defences and the rapid depletion of America’s stockpile of interceptors.

Patriot Interceptors in Short Supply

The Pentagon has used more than 1,500 Patriot interceptor missiles during the war and has fewer than 1,700 remaining, according to two people briefed on stockpile levels who spoke anonymously because they were discussing sensitive military information. The US produced about 600 Patriot interceptors during the whole of 2025.

On one day during the deadly week in Jordan, American forces in the Middle East fired about 50 Patriot interceptors, according to two US officials.

Seth G Jones, president of the defence and security department at the Center for Strategic and International Studies, told The New York Times that Iran’s combination of missiles and drones was making air defence increasingly difficult. “The Iranians are making it more difficult on air defenses when you have a range of both missiles and drones coming in,” he said. “They have effectively leveraged the Russian tactic,” he added, “to make it more difficult to protect across locations in the Gulf.”

Russia has used combinations of ballistic and cruise missiles to distract Ukrainian air defences before sending in waves of drones.

Iran Adapts Its Tactics

The attacks in Jordan are part of a wider pattern in which Iranian forces have adjusted their tactics during the conflict. US and Israeli forces heavily bombed Iran’s missile sites during the first five weeks of the war. Many Iranian missiles and launchers were stored in underground facilities.

Iran has since rebuilt or reopened many of those sites and resumed missile attacks, while also threatening shipping in the Strait of Hormuz.

Defence Secretary Pete Hegseth said on 8 April that Iran’s missile programme was “functionally destroyed”, describing its launchers and missiles as “depleted and decimated and almost completely ineffective”.

But Iran’s subsequent attacks have challenged that assessment.

Vali Nasr, a professor at the Johns Hopkins School of Advanced International Studies, told NYT that President Donald Trump and his national security advisers had expected the conflict to be relatively short and had not anticipated such pressure on the Pentagon’s stockpiles of Patriot interceptors.

Iranian officials, he and other experts said, had been preparing for the possibility since the conflict began more than five months ago.

During a 12-day war in June 2025, Iranian leaders saw how quickly Israeli and US forces used ballistic missile interceptors to defend against Iranian missile and drone barrages.

Deadly Strike on US Base in Jordan

The 17 July attack targeted Muwaffaq Salti Air Base in Azraq, a Jordanian military facility that has increasingly become a major US hub for dozens of aircraft and several thousand service members.

US troops previously stationed in Kuwait, Bahrain, Qatar and the United Arab Emirates were moved before and during the war to bases such as Muwaffaq Salti, which were considered farther from Iran and less vulnerable to drone and ballistic-missile attacks.

After the strike, US military commanders strengthened air defences in Jordan and elsewhere in the region, according to a senior US military official who spoke anonymously about operational matters.

US military specialists who have studied drone and missile attacks in Ukraine have also been working with US Central Command for months, sharing lessons from the conflict.

Two of the three soldiers killed in Jordan were assigned to air-defence units based in Germany that had become part of that effort.

F-15 Jet Also Shot Down

Iran’s ability to adapt was demonstrated earlier in the war. In April, Iranian forces shot down a US F-15E fighter jet over southern Iran using a shoulder-fired surface-to-air missile.

Both crew members ejected. The pilot was rescued quickly, while the weapons officer remained missing for almost two days before US Special Operations forces rescued him.

A senior US military official said Iran had learned from the war in Ukraine and deployed a swarm of drones in an area penetrated by American fighter jets. Pentagon officials said the F-15E’s defensive systems gave its crew only half a second of warning before the $60m aircraft was hit.

According to a senior US military official, the drones provided Iranian commanders with three crucial pieces of information: the aircraft’s GPS location, speed and direction.

Trump announced a “pause” in the fighting shortly afterwards. Two US military officials said commanders needed time to adjust to Iran’s changing tactics.

Regional Allies Urge Caution

The growing pressure on US air defences has also had wider geopolitical consequences.

In late July, Trump asked Hegseth about dwindling American weapons supplies, according to US officials, confirming earlier reporting by The Washington Post.

The Pentagon has denied that the US is facing a shortage. “Claims of US munition shortages are false,” Pentagon chief spokesman Sean Parnell said. “When the fake news media irresponsibly amplifies these lies, the real-world consequence is clear: Our enemies are emboldened to provoke — or attack — American troops.”

Two weeks ago, Trump called off bombing raids against Iran after saying the leaders of Saudi Arabia, the United Arab Emirates and Qatar had urged him to pursue diplomatic talks.

The war has killed an estimated 1,700 Iranian civilians.

Saudi Arabia’s ruler Mohammed bin Salman warned Trump that major US air strikes could prompt Iran to retaliate against energy facilities and other infrastructure in Saudi Arabia and neighbouring countries, according to a Saudi official who spoke anonymously about confidential discussions.

With US interceptor supplies under pressure and Iran demonstrating an ability to penetrate American defences, the risk of serious damage was real, the official said.

Houthis Widen Threat

Iran’s strategy has also expanded beyond direct attacks. When the Houthi militia in Yemen entered the war last month, experts said it showed Iran’s intention to force the US and its allies to defend against aerial attacks from multiple directions.

Yemen lies hundreds of miles south of Iran. The involvement of the Houthis, alongside Iranian-backed militias in Iraq and other allies, has widened the battlefield and increased the pressure on US air defences across the Middle East.