Strait of Hormuz' shipping lane is two miles wide - for ALL shipping, not just the US Navy.  The territorial waters around all countries was set at 12 NM by the UN.  Iran's always been a rascal - and wants to block the strait from international shipping.  One of the USN's responsibilities has always been to protect the sea lanes - for all, including 40% of the world's daily oil tanker traffic.  Susan Simpson's The View from LL2 blog here:  https://viewfromll2.com/2012/01/07/is-the-strait-of-hormuz-governed-by-treaty-or-by-customary-international-law/