Satellite images of al Assad air base in Iraq taken Jan. 8 show damage from Iranian missiles. Planet Labs/Middlebury Institute

Satellite images reveal damage at two bases in Iraq after Iran fired more than a dozen missiles at U.S. troops and coalition forces Tuesday in retaliation for a U.S. drone strike days earlier that killed Qasem Soleimani, one of Tehran's most powerful military officials.

The missiles targeted al Assad air base in Iraq’s Anbar province and another base in Erbil in Iraq’s semiautonomous Kurdish region.

Al Assad air base is in western Iraq and was used by American forces after the U.S.-led invasion that toppled dictator Saddam Hussein in 2003. It houses about 1,500 U.S. and coalition personnel. President Donald Trump made a surprise visit there in late 2018 and spoke about the fight against the Islamic State.

No U.S. or Iraqi troops were killed or injured in Tuesday's attack, Trump said Wednesday in a live address to the nation. He described the damage done by the missiles as "minimal." Iran, Trump said, "appears to be standing down."

A U.S. official, who was not authorized to speak publicly, stated that a hangar was damaged at al Assad.

The official described the attack as "massive" and cautioned that the assessment was made during predawn hours Wednesday.

Examination of satellite images by USA TODAY shows damage to multiple buildings at the complex.

The strike Tuesday could have functioned as a very loud warning shot and may be an indication that the Iranian regime wants to limit escalation, said Michael O'Hanlon, a military analyst at the Brookings Institution. The opening may be short-lived, he said.

"They missed on purpose and want to de-escalate – for the moment," O'Hanlon said.

The Iranians know how to hit a target when they want to destroy it, said a U.S. official with knowledge of Iranian capabilities who was not authorized to speak publicly. Such an attack would have caused "grave damage," the official said. It is possible that more moderate elements in the Iranian government are pushing for restraint, the official said.