In 2013, China’s president, Xi Jinping, launched a massive reclamation and construction campaign on seven reefs in the Spratly Islands in the South China Sea. Beijing insisted that its actions were responsible and in accord with international law, but foreign critics questioned Xi’s real intentions. Recently available internal documents involving China’s leader reveal his views about war, the importance of oceans in protecting and rejuvenating the nation, and the motives underlying his moves in the South China Sea. Central to those motives is China’s rivalry with the United States and the grand strategy needed to determine its outcome. To this end, Xi created five externally oriented and proactive military theater commands, one of which would protect newly built assets in the South China Sea and the sea lanes – sometimes referred to as the Maritime Silk Road – that pass through this sea to Eurasia and beyond. Simultaneously, China’s actions in the Spratlys complicated and worsened the US-China rivalry, and security communities in both countries recognized that these actions could erupt into armed crises – despite decades of engagement to prevent them. A permanent problem-solving mechanism may allow the two countries to move toward a positive shared future.