The consequences and implications of China’s rise have been analyzed and discussed from a number of perspectives. There has been little analysis that specifically evaluates the implications for the Atlantic Alliance, however, and whether an international system defined by U.S.-China bi-polarity would lead to a strengthening or a weakening of the transatlantic relationship. This article argues that China’s rise will create security dynamics that likely will lead to a weakening of the Atlantic Alliance. It is unlikely that China’s rise will provide NATO with a renewed purpose or give a convincing rationale for alliance cohesion the way the Soviet Union once did. Instead, China’s rise will reveal divergent strategic interests and priorities among the members of the Atlantic Alliance, with a real possibility that America’s rebalancing toward the Asia-Pacific could intensify perceptions on both sides of the Atlantic of NATO’s declining geopolitical value and relevance.