Japanese containment of China hinges on confidence in American reliability and cost.

Evidence

The core of any meaningful effort to balance and contain China would have to be the American-Japanese military alliance. Conceivably Japan might slowly acquiesce in redirecting the alliance to this purpose. Its doing so would depend upon Japan’s having confidence in: (1) the overall American ability to sustain itself as the world’s only superpower and to maintain its active leadership in world affairs; (2) the American commitment to maintain its presence in Asia and actively to combat China’s efforts to expand its influence; and (3) the ability of the United States and Japan to contain China without high costs in terms of resources or high risks in terms of war. — Samuel P. Huntington, The Clash of Civilizations and the…, 645