Relevance: GS II (International Relations) & GS III (Security) | Source: Indian Express

1. What is the Big News?

In March 2026, a major event shook the Indian Ocean. A United States submarine fired a torpedo and sank an Iranian warship, the IRIS Dena, near the coast of Sri Lanka.

• A Rare Attack: This is a highly unusual event. It is the first time since World War II that a US submarine has sunk an enemy warship using a torpedo.
• The Diplomatic Shock: The Iranian ship was not fighting. It was peacefully returning home after participating in a friendly naval exercise (MILAN-2026) hosted by the Indian Navy. Over 80 sailors tragically lost their lives.

2. How Does a Torpedo Sink a Ship? 

The US submarine used a heavy weapon called the Mark-48 torpedo (weighing about 1,700 kg). To understand its destructive power for your notes, look at how it works:

• The Deep Dive: Instead of hitting the side of the ship like a bullet, the torpedo uses sound waves (sonar) to swim deep underneath the target ship.
• Breaking the Spine: It explodes exactly under the center bottom (the keel) of the ship. This massive underwater explosion creates a giant bubble of hot gases.
• The Result: The bubble violently pushes the center of the ship upwards while the front and back fall down. This literally snaps the ship’s heavy metal spine in half, causing it to sink instantly.

3. Is this Legal? (The Rules of Sea War)

When a country attacks a ship, lawyers look at international rules:

• The UNCLOS Gap: The United Nations Convention on the Law of the Sea is the main ocean law. However, it only manages the sea during peacetime (like fishing or trade rights). It does not have clear rules for active wars.
• The EEZ Loophole: The ship was sunk inside Sri Lanka’s Exclusive Economic Zone (EEZ). While Sri Lanka has the sole right to catch fish or find oil here, foreign militaries still treat the EEZ as “international waters” where they can legally fight.
• Legitimate Target: Under the customary Law of Naval Warfare, once two countries are at war, an enemy warship is always considered a legal target to destroy, even if it is just sailing peacefully.

4. Why is India Worried?

• Loss of Trust: Attacking a ship right after it leaves a friendly diplomatic event hosted by India breaks the unwritten rules of strategic trust.
• War at our Doorstep: This proves the Indian Ocean is slowly turning into an active war zone. India must heavily increase its Maritime Domain Awareness (keeping a strict watch on all foreign ships and submarines) to protect our trade routes.

UPSC Value Box

With reference to international maritime laws and naval warfare, consider the following statements:

1. The United Nations Convention on the Law of the Sea (UNCLOS) contains comprehensive and strict guidelines for conducting naval warfare between two countries.
2. A foreign military submarine has the right of freedom of navigation within the Exclusive Economic Zone (EEZ) of another coastal state.
3. A modern torpedo primarily destroys a warship by causing a direct impact explosion on the side armor of the ship above the waterline.

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 2 only

(c) 1 and 3 only

(d) 1, 2 and 3

Correct Answer: (b)