Iran's network of underground missile facilities survived months of U.S. and Israeli airstrikes earlier this year and remains a key component of Tehran's military strategy, according to Iranian officials, Western diplomats, and analysts.

The resilience of Iran's so-called "missile cities" has emerged as a major point of debate following a 40-day bombing campaign targeting missile infrastructure across the country, including a heavily fortified complex near the central city of Yazd, reports The Financial Times on Friday.

Residents and analysts said Iran continued launching missiles throughout the conflict, even as U.S. and Israeli forces repeatedly struck missile sites.

"U.S. and Israeli forces kept bombing those mountains," a Yazd resident said. "And Iran kept launching missiles until the final moments before the ceasefire."

President Donald Trump had vowed at the start of the campaign to destroy Iran's missile capabilities, saying the United States would "raze their missile industry to the ground."

Israeli officials later said most Iranian launchers had been taken out of operation.

However, U.S. intelligence assessments cited by American media outlets reportedly found that Iran retained about 70% of its mobile missile launchers and roughly 70% of its prewar missile stockpile.

The assessments also indicated Tehran had restored access to many missile sites and underground facilities, including locations near the Strait of Hormuz.

A senior Western diplomat in Tehran said those estimates were broadly consistent with his own assessment.

"We believe they have protected a significant portion of their arsenal and capability," the diplomat said. "The entrances to some tunnels were bombed, but they could dig themselves out."

Iranian officials contend the war reinforced the leadership's belief that military strength, rather than diplomacy, is the country's primary safeguard against external threats.

A person described as close to Iran's leadership said the conflict strengthened confidence in the country's military posture and deterrence capabilities.

The individual said the Yazd missile complex extends hundreds of meters into surrounding granite mountains and remained operational throughout the conflict. While some tunnel entrances were damaged, he said they were reopened quickly.

Analysts said Iran's strategy of dispersing and burying missile infrastructure deep underground helped preserve much of its missile force.

Sam Lair, a researcher at the James Martin Center for Nonproliferation Studies, said Iranian missile launches declined during the heaviest phase of the campaign, suggesting U.S. and Israeli suppression efforts had some success.

"But if you think about this in kind of a broader timeline, then the missile cities have succeeded in preserving a large portion of the Iranian missile force," Lair said.

Nicole Grajewski, an assistant professor at Sciences Po, said evidence suggested Iran restored access to damaged facilities more quickly than many observers expected.

"We only discovered that during the later stages of the war because there'd be persistent strikes on a certain base and then Iran would fire from there," Grajewski said.

She said repeated patterns of strikes followed by missile launches could indicate rapid excavation efforts, repairs, or the use of decoys.

"The rapid kind of turnaround on cleaning up the missile bases during the war, at least enough to lob some missiles and make it operational, was very impressive," she said.

Analysts estimate Iran operates dozens of underground missile facilities across the country, many built deep inside mountainous terrain.

Decker Eveleth, an associate research analyst at the Center for Naval Analyses, said facilities near Iran's western border were more vulnerable to surveillance and attack, while sites deeper inside the country were harder to suppress.

"The problem for the U.S. and Israel has been that the things needed to pin down a lot of these bases require a lot of continuous operations," Eveleth said.

Iran's missile program has increasingly relied on underground facilities and decentralized operations over the past two decades, partly to compensate for weaknesses in its air force and air-defense systems.

Analysts said the conflict is likely to strengthen the role of Iran's Islamic Revolutionary Guard Corps, which oversees much of the missile program.

"Today the guards are stronger than they were before the war," a person close to the Iranian regime said. "Their standing within the system has risen dramatically because they fought under extraordinary pressure and continued launching missiles until the final moment."