Prior to the Opium War China was central to Pacific Asia, but it was not in control of its neighborhood. The mobility of the various nomadic groups threatened China’s northern and western frontiers, and Vietnam’s successful resistance to Ming annexation set a southern boundary-stone. While China’s centrality was not hegemonic, its location, demographic preponderance, and artisanal production made China the center of regional attention. Conversely, because of China’s demographic and production centrality, China was more interested in defending what it had than in imperial adventures abroad. Its foreign policy was one of controlling exposure in relationships—thin connectivity. By the Ming Dynasty this evolved into the tribute system, whose core was a ritualized exchange of deference by the neighbor for acknowledgement of autonomy by China.