The U.S.-Japan Mutual Security Treaty ("The Cooperation and Security between the United States vides in Article VI that "for the purpose of contributing to the and the maintenance of international peace and security in United States of America is granted the use by its land, air an facilities and areas in Japan."
Giarra, Paul S.
"Host Nation Support, Responsibility Sharing, and Alternative Approaches to U.S. Bases in Japan,"
Naval War College Review: Vol. 50:
4, Article 6.
Available at: https://digital-commons.usnwc.edu/nwc-review/vol50/iss4/6