This unit can fire both types of missiles. Tactical missiles are built and launched automatically, but strategic (long range nuclear) missiles must be constructed before launching. In Forged Alliance, strategic missiles can be built while the sub is moving, so it is wise if your economy can handle it to begin building these missiles right away. Because of the long build time, it is now unwise to assist a strategic missile sub in building its strategic missiles. Think of the sub as a mobile strategic missile silo, much less vulnerable to gunships and bombers, and a lot less likely to be discovered if hidden.