According to naval watchers, the explosion itself was enough to sink the ship, and hence, there was no need to fire a torpedo, which led casualty figures to rise.
"From the video released by the Pentagon, it is apparent that the ship was already on fire, presumably hit by a missile fired from a standoff range by the same submarine. However, since the missile hit is above the waterline, it only damaged the warship and did not sink it," Captain Anurag Bisen, a veteran submariner of the Indian Navy, currently a senior fellow at the prestigious Vivekananda International Foundation (VIF) in Delhi, told Sputnik India.
The connotation is that the American crew was fully aware that the Iranian ship did not pose a threat to the submarine. While the objective of war is to put your enemy out of the way, this was already achieved by firing the missile at the ship, disabling it in the process, the former Indian Navy official explained.
"If the Americans wanted to further disable the ship, they could have fired at the front part of the warship, which would not have led to the sinking of the ship and loss of so many lives. It is not a military logic to sink this vessel, but it reflects a perverse mindset and could be construed as a premeditated or cold-blooded murder," Bisen reckoned.
This act of firing at the Iranian ship is in conflict with international law. The guiding principles of the Geneva Convention and the law of the armed conflict regarding the use of force are necessity and proportionality, unless it is an act of self-defence, he noted.