This article brings an international relations perspective to the discussion of the science and policy of avoiding a Sino-US arms race in space. A blind adherence to realist and space nationalist assumptions, without considering alternative approaches such as the policy options offered here, will likely doom China and the United States to a long, expensive, and potentially dangerous arms race in space for decades to come. KEYWORDS: US-China relations, arms control, space security, Chinese military, international relations, East Asian security. "WHO CONTROLS LOW-EARTH ORBIT CONTROLS NEAR-EARTH SPACE.WHO controls near-Earth space dominates Terra [Earth and atmosphere]. Who dominates Terra dominates the destiny of humankind. . . . The United States is the morally superior choice to seize and control space" (Dolman 2002, 2005). Statements such as Everett Dolman's embody an approach to space security that makes war and conflict in space almost inevitable, and they certainly have ominous implications for the future of Sino-US relations.Most experts on space security agree that space has not been weaponized to date (O'Hanlon 2004; Moltz 2008), and while terrestrial weapons can strike space assets and while space assets are used in targeting for terrestrial weapons with terrestrial targets, there are as of yet no weapons located in space, whether those of China or the United States. Yet how long can this last?While five of the six previous articles in this collection are authored by physicists or engineers with technical expertise in matters of space weaponry (Grego, Shen, Chen, Wu, and Gubrud), this article is an attempt to bring a political science/international relations (IR) perspective to discussion of the potential and dangers of a Sino-US extraterrestrial arms race, and prospects for avoiding it. The article poses several questions. As China continues to rise economically and militarily, is an arms race or even a conflict in space between the United States and China inevitable? What role do one's theoretical lenses have regarding views of the inevitability of an extraterrestrial Sino-US arms race or conflict in the future? Is there a realistic basis for seeking common ground between the United States and China on these issues, so that an arms race and conflict in space might be avoided? The Very Real Potential of a Sino-US Extraterrestrial Arms Race The Imbalance of Capabilities To begin the discussion, it should be noted that the possibility of a Sino- US arms race in space is related to the larger phenomenon of the rise of China and the transmutability of economic power into political and military power. In 2010 China surpassed Japan as the world's secondlargest economy, behind only the United States. In the last couple of years, China has also become the world's largest new car market, surpassing the United States, and the world's number-one producer of greenhouse gases. Although China has the world's largest population, comparing its gross domestic product (GDP) per capita with the United States put things in a more realistic perspective-based on 2011 figures from the International Monetary Fund, US GDP per capita is $48,655 and China's is $7,519-there is little doubt that the most significant international relations story of the twenty-first century is the rise of China as a global power and the manner in which the world's reigning superpower, the United States, reacts to that new reality. Given the growing importance of space to both countries, the way in which they manage their presence there will be a fundamental part of their relationship in coming decades. Presently, the United States has an undeniable and almost unchallenged position of space primacy. For example, at the time of writing (June 2011), according to Union of Concerned Scientists data, of the 957 operating satellites in orbit around the Earth, 436 (45.6 percent) are from the United States, 100 (10.4 percent) are from Russia, and 69 (7. …