A Ballistic Missile Submarine (BMS) is a type of submarine designed to carry and launch ballistic missiles. These submarines are a key component of a nation's nuclear deterrent strategy, allowing for stealthy and secure deployment of nuclear weapons. They can operate underwater for extended periods, making them difficult to detect. BMS are equipped with multiple missile launch tubes, typically housing intercontinental ballistic missiles (ICBMs) like the Trident II. Countries such as the United States, Russia, and China maintain fleets of these submarines to ensure a second-strike capability in the event of a nuclear conflict.