The sinking of ‘Iris Dena’, an Iranian Navy Destroyer, by a United States (US) submarine off the coast of Sri Lanka in the early hours of Wednesday marks a dangerous new turn in the conflict between Israel-US and Iran, which is barely one week old. According to US Defence Secretary Pete Hegseth, this is the first time since 1945 that a US Navy submarine used a torpedo (as opposed to a surface weapon) to attack and destroy a vessel in