A third potential security danger is that accommodation by the United States could undermine its allies’ assessments of the credibility of the United States to come to their aid if attacked by China. More specifically, critics believe that ending the U.S. commitment to Taiwan could lead the Japanese to doubt America’s commitment to defend Japan, which would undermine the U.S.-Japan alliance and in turn reduce U.S. security. Tucker and Glaser argue, “A U.S. decision to abandon Taiwan—leading to unification of an unwilling Taiwan with China— would be particularly alarming to Japan. . . . If Japan begins to doubt U.S. reliability, that could deal a fatal blow to the U.S.-Japan alliance.”97 Although a decision by the United States to end its commitment to Taiwan would certainly send political shock waves across the region, these concerns are overstated. There are similarities between the U.S. commitments to Taiwan and Japan, but also clear differences. U.S. security interests in Japan are much greater; as a result, the alliance involves much stronger political commitments and the deep integration of U.S. and Japanese military capabilities.
A U.S. decision to abandon Taiwan would be particularly alarming to Japan. . . . If Japan begins to doubt U.S. reliability, that could deal a fatal blow to the U.S.-Japan alliance these concerns are overstated U.S. security interests in Japan are much greater; as a result, the alliance involves much stronger political commitments and the deep integration of U.S. and Japanese military capabilities