(THAAD) missile systems for ballistic missile defense out to ranges considerably beyond Patriot are expected to reach Army field units in 2001.2

Limited funding and technical uncertainties have delegated three other ballistic missile defense programs to longer-term development. The Corps SAM (surface-to-air missile) program would provide mobile ATBM capabilities to U.S. Army forces. Either sea-based THAAD or the addition of Aegis ATBM missiles with LEAP (lightweight exo-atmospheric projectile) capabilities would give the Navy “upper tier” ATBM capability above the currently planned Aegis ATBM missiles. Finally, several options exist for a boost/ascent-phase ballistic missile intercept capability. 3


Concern about possible ballistic missile threats in Japan has been prompted primarily by the activities of North Korea.4 In addition to concerns about its efforts to produce nuclear weapons, North Korea is also developing ballistic missile capabilities that would enable it to attack Japan. In May of 1993 North Korea test fired a ballistic missile 500 km into the Sea of Japan. This missile, Nodong-1, is believed to be capable of carrying a nuclear warhead and to have a range in excess of 1000 km, allowing it to strike western Japan. While some military experts question whether North Korea will be successful at developing and deploying a ballistic missile capable of delivering nuclear, chemical, or biological weapons, it would seem prudent for Japan to consider such a possibility.5 Furthermore, while Japan currently enjoys stable relations with Russia and China, both nations possess nuclear ballistic missiles capable of striking Japan.

Japan already possesses or is procuring some rudimentary elements of a TMD system.6 Patriot PAC-2 missile units are currently deployed in the air-defense role. Japan also has Aegis air defense systems and is procuring AWACS aircraft, both of which could be used as part of a TMD system. Nevertheless, each of these weapons systems would require upgrades to perform TMD functions. Furthermore, these assets might not be available for their current missions if they were deployed in a TMD role in the future.

Japan also has an indigenous development program known as “Future SAM” under way to develop medium-range surface-to-air missiles to replace U.S.-supplied Hawks currently used in the air-defense role. Future SAM, with production delivery scheduled to begin by the end of the decade and a total cost estimated at $4.8 billion, might play a role in a future TMD system.7

U.S.-Japan collaboration in the ballistic missile defense area goes back to the late 1980s, when several Japanese companies received contracts from DoD as part of the WESTPAC project, an initial study of ballistic missile defense requirements in the Western Pacific. 8 The Japanese government did not officially participate in WESTPAC.

Last year U.S. defense officials reportedly discussed a series of four possible TMD “options” with Japanese officials.9 Although the options discussed in 1994 have been superseded by an






Susumu Awanohara, “My Shield or Yours?”, Far Eastern Economic Review, October 14, 1993, p. 22.


“North Korean Missile Eyed with Skepticism,” Aviation Week and Space Technology, October 18, 1993, p. 101.


Awanohara, op. cit.


“North Korean Missile Eyed with Skepticism,” Aviation Week and Space Technology, op. cit.


Hironobu Sakamoto, “Japanese Firms Win SDI Research Contracts,” Japan Economic Journal, December 17, 1988.


Naoaki Usui, “Japan Tackles Antimissile Options,” Defense News, August 29, 1994, p. 1.

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