Article 9 of the Japanese Constitution prohibits the existence of Japanese military forces. Japan has a treaty of mutual cooperation and security with the United States, which commits the US to defending Japan. Because of an ongoing moratorium on the export of weapons abroad, Japan’s defence industries are suffering under the effects of limited collaboration opportunities and limited markets for their products. However, the Japanese Government is exploring ways of opening up new markets for Japanese defence companies as well as loosening the constitutional restrictions on Japan’s military. Find out more about Japan's security sector below.