Talk about mixed signals. Last week, Chinese leader Xi Jinping announced a 300,000-man reduction in the size of the People's Liberation Army — a decision at least partly calculated to look like China has no aggressive intentions toward the rest of the world. Yet at almost the same time, he sent five Chinese ships into the Bering Sea near Alaska, in an unprecedented maneuver timed to coincide with the last day of U.S. President Barack Obama's visit to the state. This sort of symbolism is pretty close to the textbook definition of muscle-flexing aggression.

So what's going on? Is Xi being peaceful or being hostile? The answer is complicated — but so are the circumstances of the cool war between China and the United States. Domestically, Xi wants to signal that he has control over the military, that reforms are needed and under way, and that China won't waste money on a land force that has little to do with its strategic position. Although these moves aren't exactly pacifist, at least they aren't warmongering.

Simultaneously, Xi wants to signal to both his domestic and his foreign audiences that China will continue to press for a global strategic advantage against the U.S. by focusing its military efforts where the U.S. hasn't asserted its own power.