1. The Rules of the Sea: The 1991 Treaty

To prevent accidental wars, India and Pakistan signed a crucial military communication treaty in April 1991. Here is what it demands:

• The 3-Mile Buffer Rule: The treaty strictly states that naval ships and submarines from both nations must never come closer than 3 Nautical Miles (about 5.5 km) to each other to avoid physical crashes.
• No Surprise Attacks: Both countries must warn each other before conducting major military drills at sea. This ensures that neither side mistakes a training exercise for a real invasion.
• The Right to Question: If India sees suspicious Pakistani ship movements, the treaty gives New Delhi the legal right to demand a formal explanation about where those ships are going and why.

2. Why Was This Treaty Created?

This agreement was born out of intense military paranoia during the 1980s.

• Operation Brass Tacks (1987): India conducted a massive military drill involving 150,000 troops near the border. It spooked Pakistan so badly that both nations nearly went to war, forcing them to create better communication rules.
• The Nuclear Fear: By the late 80s, both countries were secretly developing nuclear weapons. A simple misunderstanding at sea could have triggered a catastrophic nuclear war, making these safety pacts essential.