The United States shoulders the costs of operating and maintaining its ships and planes stationed in Japan as well as the salaries, supply and transportation needs for American troops. So far the total SMA costs for Japan have averaged less than one quarter of 1 percent of its national budget. The United States, in contrast, spends about 3 percent of its gross domestic product on maintaining its defense capabilities. The United States considers Japan an equal partner in maintaining Asia-Pacific stability, but each country makes different but complementary contributions to that partnership. Japan provides for its own defense forces and, through multilateral channels, supports crisis management and nation-building efforts around the world.
Japan also provides huge amounts of foreign assistance in support of regional security.
In particular, Japan has contributed millions of dollars to support nuclear nonproliferation efforts on the Korean Peninsula. In 1998, North Korea fired a short-range ballistic missile over the Japanese mainland and into the Pacific Ocean, raising concerns across Asia. In 1999, North Korea threatened to test-launch a more advanced missile with a longer range and greater accuracy. More than one million North Korean troops serve on active duty, the vast majority deployed within hours of the demilitarized zone separating the two Koreas. North Korea continues military infiltration efforts into South Korea and has threatened to walk away from the Agreed Framework it signed with the United States in 1994 that curtails its nuclear production program.