Constitutional reform is a controversial issue in Japan. Diet members are tackling the controversial issue of the constitution's Article 9 (which forbids Japan to maintain military forces-interpreted as offensive military forces). The future of Article 9, however, is one of the most important and controversial issues in constitutional revision debates. Most Japanese agree that the constitution forbids offensive potential but allows the right of self-defense. This interpretation has led to several types of weapons systems being considered as unconstitutional, such as aircraft carriers, long-range bombers, and ICBMs. Also unconstitutional is the dispatch of armed forces to other territories for the purpose of using force. Collective self-defense is also seen as prohibited. Finally, over the years Japan has adopted three ”non-nuclear” principles.