Key Points

• China, Taiwan, Vietnam, the Philippines, Malaysia, and Brunei have used a wide variety of tactics to protect and advance their maritime territorial claims in the South China Sea. China is the most active user of the nine categories of tactics identified in this paper, with the exception of legal actions, and accounts for more than half of all military and paramilitary actions since 1995. 
• Empirical data support the argument that the 2011 U.S. rebalance to Asia did not spur disruptive behavior in the South China Sea. China became more active in protecting and advancing its claims around 2009, before the rebalance was announced. 
• The unclassified database used in this analysis undercounts military and paramilitary actions, but captures enough activity to provide a representative sample. A classified version that captures more activity would improve the potential to develop the database into an Indications and Warning tool to assist in monitoring and managing tensions in the South China Sea.