Trump says "US must respond".

https://www.theguardian.com/world/live/2026/jun/09/middle-east-crisis-iran-israel-us-donald-trump-strait-of-hormuz-peace-deal-latest-news-updates

In a statement on Truth Social, Trump said he had been informed “that last night the Iranians shot down one of our highly sophisticated Apache Helicopters while patrolling over the strait of Hormuz.”

While the pilots were uninjured, “the United States must, of necessity, respond to this attack.”

Hmmmmm. Very much depends on what they mean by "shot down".