Despite tensions between the United States and China over the South China Sea, the two nations' militaries train together at a very high level. Current "mil-mil" engagements are robust, with China participating in the world's largest international maritime exercise, RIMPAC 2014, which is hosted biannually by the U.S. Pacific Command. The drills allowed China to learn a great deal about U.S. tactics, techniques and procedures (in military shorthand, "TTPs").

But even as the U.S. provided China with its highest-level access to military drills, the U.S. military leadership consistently ratcheted up the level of confrontation in the South China Sea. Most recently, a top U.S. Navy admiral participated in a surveillance flight in the region. The U.S. is at once inching closer to armed confrontation, while at the same time training Chinese forces in the American way of war.

RIMPAC is one of many occasions when U.S. forces have trained their Chinese counterparts. China has participated in U.S.-led counter-piracy operations in the Indian Ocean since 2008. Initially, due to language difficulties and unfamiliarity with American and allied forces tactics, techniques and procedures, China was given a separate area to patrol. But over the last seven years, cooperation has become closer, as the U.S. sought greater coordination of operations and closer relations with Chinese ships, by conducting combined exercises in 2013 and again in 2014.