Mark, I had a friend who once revealed something he shouldn't have. It was in the very early 1970s when he told me. The story came out - sort of - in the late 1990s. He told me that a short while before when he was a navy diver working from the USS Barbel they had been rammed accidentally by a Chinese ship while "up a river in North Vietnam." He said they were very afraid they would not escape, that the Barbel would sink where it was. They did escape. The Navy now admits that the Barbel was struck by a ship while it was trying to determine what was aboard the ship. The location is given as "off Hainan Island." North Vietnam is "off" Hainan. I do not think the USN will readily admit to an incident such as this anymore than it publicly admits to some SEAL penetrations of critical facilities, including ship reactor rooms in the past. The lessons will be learned. If the Iranians did this, then they have given away an advantage we will learn from.
IDF strikes Gaza targets in response to rocket fire (Haaretz)
from the article: Iran Revolutionary Guards: Unit engraved emblem on U.S. ship