Late to the subject and Im not going to address the political stuff within this thread , just want to clear up some things about the actual attack.
In these types of operations simple is best, think KISS.
Guarantee that limpet mines where placed on the hulls when these ships where in port and timed to explode when the ships would be most likely at sea.
Simple, KISS operation: Several combat swimmers ride the tide under the ship, place the mines and continue with the tide to a safe distance away to exit the water to be picked up by a boat. Pretty easy as security in many foreign ports is very weak.
Conducted at night with rebreathers and it would be very hard to detect anything amiss.
Seems to me the mines were purposely weak or ineffective and not sure of the reason for that.
Iran can certainly build capable bombs/mines and their SF troops are pretty good.

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