“We believe that this is the largest single Patriot engagement in US military history,” he told a Pentagon news briefing on Thursday, adding Qatari Patriot crews were also involved.
Gen Caine said there was “a lot of metal flying around” but didn’t offer specifics.
“I’m not going to tell you how many rounds were shot, but it was a bunch, because of classified purposes,” he told reporters.
Gen Caine said 44 American soldiers were responsible for defending the base, with the youngest 21 and the oldest 28.
He added the troops only had “approximately two minutes” to “either succeed or fail” due to the speed that ballistic missiles travel.
“They are the unsung heroes of the 21st century United States Army,” he said.
“Simply stated, they absolutely crushed it.”
Patriot is a surface-to-air system that Ukraine has used extensively to defend itself against Russian missile strikes.
Mr Trump said Iran gave advance warning of the attacks, with 13 of the 14 missiles intercepted and one was allowed to land because it was heading in a “non-threatening direction”. No injuries were reported.
Gen Caine revealed that US troops had been moved away from Al Udeid after learning of Iran’s intention to launch the attack.
“We assumed a minimum force posture,” he said.
Mr Trump claimed the US action on Iran, which involved 14 30,000lb bunker busters, had “obliterated” Iran’s nuclear facilities.
Appearing alongside Gen Caine on Thursday, defence secretary Pete Hegseth defended the strikes despite leaked initial intelligence assessments that suggested they had failed to destroy some key facilities.
He criticised reporters for “breathlessly” focusing on that “preliminary” assessment and said such stories were just attempts to undermine Mr Trump.