its also the sovereign waters of oman as well, its just oman outsources its military to the USA, who didn't have the ability to enforce its sovereignty.

But this was a know risk, and there are at least 20 years of plans, thoughts risk assessments for the Strait of Hormuz. Had the state department not fired everyone, or the DoD not fired all its strategic advisors, they'd have been able to tell the exec all of these problems.