A missile boat or missile cutter is a small warship armed with anti-ship missiles. Being a small craft, missile boats are popular with nations interested in forming an inexpensive navy. They are similar in idea to the torpedo boats of World War II; in fact, the first missile boats were modified torpedo boats replacing two or more torpedo tubes with missile tubes. The doctrine behind the use of missile boats is based on the principle of mobility over defence and firepower. The advent of proper guided missile and electronic counter measure technologies gave birth to the idea that, because a guided missile (such as a guided artillery shell) is far more accurate than an unguided missile (such as an unguided artillery shell), warships should now be designed to outmaneuver their enemies and get to a better position first.