The truth that Iran doesn’t want to admit is that their only ability to annoy ships in the Gulf is through terroristic action - any organized military operations will find themselves in a shallow grave, on ground, or in the water. Portable missile launchers is about the only thing that will have any effect, and most of those missiles are threats only to oil carriers. A US Navy escort should be able to block any possible hits on the carriers.
Missiles launched at our fleet en masse from shore could be a concern as well. ....especially their new Russian-made SSN-X-26 Yakhont cruise missiles.
Missles yes but what about a few batteries of 155mm's? From shore, they can cover both shipping lanes in the Strait.
Their most serious threat (and since World War II, this has done the most damage to the US Navy everywhere) is mines.
And a truly massive small boat swarm is more problematic than you’d think.