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A Sample Focus Piece from International Boundary Monitor (15 August 1998),
by International Boundary Consultants
American Defense Commitments and Asian Island Disputes

US defense agreements with Japan and the Philippines could embroil America in three island disputes and, in theory, lead to armed conflict with China, Malaysia, Taiwan, or Vietnam. Japan disputes the Diaoyu/Senkaku islands with China and Taiwan. The Philippines contests most of the Spratly Islands with China, Malaysia, Taiwan, and Vietnam. Manila also disputes ownership of Scarborough Reef with Beijing and Taipei. The 1951 Philippine-US mutual defense treaty and the 1960 Japan-US mutual security treaty can be interpreted as pledging the US to assist these countries if they are attacked in the disputed islands. Officials of both countries have alleged this. On 12 December 1996 Japanese and Philippine officials independently claimed that their treaties with the US obligated America to aid their forces if attacked in the islands they dispute with China.[1] On 5 August 1998, Philippine Foreign Affairs Secretary Siazon said that the US is bound to help his country if attacked in the Spratly Islands.[2] 

Diaoyu/Senkaku Islands 

The Japan-US security pact clearly applies to the Senkaku/Diaoyu Islands, which have been claimed by China (and Taiwan) since the close of World War II. The US defense pact with Japan is crafted to cover areas administered by Japan.[3] No doubt, this was a clever American attempt to exclude the Northern Territories/Kuril Islands from the agreement, because they are administered by Russia. It also excludes Liancourt Rocks (Tokdo/Takeshima), which are claimed by Japan but controlled by the Republic of Korea. Although the US takes no position on the question of sovereignty over the Diaoyu/Senkaku Islands, it returned those islands to Japanese administration in the Okinawa Reversion Agreement.[4] Thus, the disputed islands fall within the area covered by the defense pact. However, the pact only obligates the US to "act to meet the common danger in accordance with its constitutional provisions and processes" and to report to the UN Security Council in the event of a threat. America is not committed automatically to "defend the islands in case of emergency," as Foreign Ministry official Masaki Orita told the Committee on Foreign Affairs of the Japanese House of Councillors in 1996. However, the question has never been explicitly addressed. Is the US obligated to aid Japanese forces on or near the disputed islands if they are attacked by China? 

Spratly Islands and Scarborough Reef 

America's commitment to defend Philippine forces in the South China Sea is more problematic. Previously, the US had tiptoed around the geographic definitions in the 1951 mutual defense treaty with the Philippines, which included the provision that

"Each Party recognizes that an armed attack in the Pacific Area on either of the Parties would be dangerous to its own peace and safety and declares that it would act to meet the common dangers in accordance with its constitutional processes. ... [A]n armed attack on either of the Parties is deemed to include an attack on the metropolitan territory of either of the Parties, or on the island territories under its jurisdiction in the Pacific or on its armed forces, public vessels or aircraft in the Pacific."[5]
  The term, Pacific Area, was left ambiguous in the defense treaty. Washington had interpreted the treaty as applying to the territory of the Philippines at the time the treaty was signed, which would exclude Scarborough Reef and all of the Spratly Islands.[6] The Philippines did not lodge its claim to most of the Spratly Islands until a 1978 Presidential Decree. Manila's claim to Scarborough Reef was not generally known before 1997. During US Defense Secretary Cohen's July 1998 visit to Manila, Foreign Affairs Secretary Saizon sought clarification and reportedly was told that the South China Sea was included.[7] It is not clear that the US has changed its interpretation of the 1951 treaty, but a joint Philippine-US live-fire exercise near Scarborough Reef during August 1998 adds to the confusion.[8] 

Often, especially in 1995 after China occupied Mischief Reef and in 1996 when the PRC promulgated straight baselines, Philippine Defense Ministry personnel have said that the mutual defense treaty pledged Washington to defend their forces if attacked by China in the Spratly Islands.[9] However, Manila's Foreign Ministry had held to the view that the treaty applied to the territory of the Philippines in 1951. Siazon's August 1998 statement seems to be a change of interpretation by the Philippine Foreign Ministry. It may also be an effort to secure passage of a Visiting Forces Agreement with the US through the Philippine Senate. If officials Philippine officials have intentionally misrepresented the US defense commitment to secure passage of the Visiting Forces Agreement by their Senate, they do a disservice to their people. 

Other Islands 

The US defense commitment to South Korea involves it in one additional set of disputed islands. The 1953 Korean Armistice Agreement placed two clusters of islands off the west coast of North Korea, the Northwest Islands, under UN control. The Northwest Islands are inhabited by South Koreans and remain a source of tension and fishing incidents between North and South Korea. 

As mentioned above, the Japan-US defense agreement applies to territory administered by Japan. That provision effectively excludes Liancourt Rocks, which are claimed by Japan but controlled by South Korea, and the Kuril Islands/Northern Territories, which are claimed by Japan but controlled by Russia. 


Confusion about where US defense commitments apply could lead to serious miscalculations by countries claiming disputed Asian islands. Japan or the Philippines could become unwarrantedly provocative if they believe that they have American backing. The other claimants--China, Malaysia, Taiwan, or Vietnam--could underestimate a US response. There are times in international relations when ambiguity serves the interests of peace and security. This is not the case with mutual defense treaties. The peoples of America, Japan, and the Philippines deserve clarity about what and where they are pledged to defend. 

   1. Tokyo Shimbun (13 December 1996, Morning Edition, p. 2; Business World (Manila, 13 December 1996), both found in US Foreign Broadcast Information Service, Daily Report: East Asia (17 December 1996).

2. Business World (Manila, Internet Version, 6 August 1998), trasncribed in FBIS-EAS-98-218.

3. Treaty of Mutual Cooperation and Security, United States Treaties and Other International Agreements [hereafter UST] (Washington, DC: Government Printing Office), Vol. 11 (1960), part 2, pp. 1632-35 [TIAS 4509].

4. Agreement between the United States of America and Japan Concerning the Ryukuy Islands and the Diato Islands, UST vol. 23 (1972), pt. 1, pp. 447-81 [TIAS 7314].

5. Mutual Defense Treaty between the United States of America and the Republic of the Philippines, UST vol. 3, pt. 3, p. 3950.

6. Manila Bulletin (Internet version, 11 May 1997), transcribed in FBIS-EAS-97-132; Manila Standard (26 May 1997, pp. 1, 4), transcribed in FBIS-EAS-97-156.

7. Business World (Manila, 6 August 1998).

8. Associated Press (Manila), 6 August 1998.

9. Daniel J. Dzurek, "China Occupies Mischief Reef in Latest Spratly Gambit," Boundary and Security Bulletin 3 (April 1995): 65-71; Business World (Manila, 13 December 1996), transcribed in FBIS-EAS-96-242; GMA-7 Radio-Television Arts Network broadcast in Tagalog, 12 May 1997, translated in FBIS-EAS-97-132. 

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Last Updated: Sunday, October 25, 1998