If correct, that would be a significant escalation?
A rather expensive and important asset...
Nope! Not at all.
It is considered a cost of doing business and can be used for political purposes after the fact to show hostile intent and culpability by Iran in the Tanker Attacks.
If the Iranians are such peace loving and kindly folk they would not interfere with anything or anyone assisting in providing security for commercial ship traffic would they especially in International Waters or International Airspace.
For sure....they have no legal justification for downing any aircraft or firing upon any vessel in International waters do they...unless one of their vessels are being attacked.
The Sanctions must be putting some real hurt on them....and the radical elements within their government must be acting out over it.