Why long-range submarine missiles still need outside targeting

Missile range does not give a submerged boat an equally long sensor horizon. A submarine must either detect and classify the target itself, receive target-quality information from another platform, or attack a fixed location programmed before launch. Firing anti-ship missiles reveals the launch area and invites aircraft, escorts, or torpedoes to converge, so a small salvo against a defended convoy may achieve little. The boat gains more by coordinating its weapons with attacks from the air and surface, but the communications needed for that coordination create another threat to stealth.