Okie dokie...... Sooooo, you honestly believe Iran could shut down the straights using their fast boats with not only the US but other nations patrolling the straights? No they couldn't nor would they as they know full well the ramifications to their own economy if they tried.
Oh and yes, we learned, they try to push the envelop but know where to back off because they know they'll be blown out of the water if they cross that line. As for an incident like that causing war (what this discussion started out as), no. Causing a limited armed response, yes.
Again you demonstrate you do not have a grasp on the larger picture.
According to the U.S. Energy Information Administration, in 2011, an average of 14 tankers per day passed out of the Persian Gulf through the Strait carrying 17 million barrels (2,700,000 m3) of crude oil. This was said to represent
35% of the world's seaborne oil shipments and
20% of oil traded worldwide.
--
https://en.wikipedia.org/wiki/Strait_of_Hormuz
Freedom of Navigation through the Strait is not only one of the US' primary goals in that region, it is the WORLD'S! 35% of all of the WORLD'S seaborne oil shipments - for nations' energy.
The reason the Iranians don't just willy-nilly declare 'The Straight is Closed' and try to enforce it because they KNOW it would be WAR...and NOT just with the United States!
And you can keep parroting your question about the small boats over and over, but I have already answered it numerous times. (If you feel like asking it again just look back at my response to the last 2 - 3 times you asked me.)
Iran would not use small boats alone. You keep ignoring the fact that they also have anti-shipping batteries along the coast in the strait that DEFINITELY can reach out and touch ships passing through the strait.
you also don't understand that IF a US ship passing through the strait was damaged (as the USS Cole was) and the Iranians declared the strait to be closed, ALL international shipping would wait at/return to the ports inside the gulf and would not pass into the mouth of the straits outside the gulf, like a hugs whipping parking lot. Lloyds of London, the primary company that insures those ships, would not let them enter a hostile area like that.
For Iran to attack a US vessel like that would be an act of war, no matter how limited or expanded, and a declaration of closing the strait is an act of war. Again, we would not be the only ones to jump on this to re-open the strait.