For decades, the hardest problem for a Chinese admiral has not been building ships but getting them out of the house. From its eastern ports, the People's Liberation Army Navy faces a necklace of islands, running from Japan through Taiwan to the Philippines, that Western strategists call the first island chain. Every strait in it is watched by American, Japanese or other regional sensors. Recent PLA exercises, as analysed by The Diplomat, suggest that Beijing is now training specifically to solve this problem.

The method is dispersal. Rather than sailing out in one conspicuous formation, task groups are reported to split up, vary their routes, limit their radio emissions and reassemble beyond the chain, in the Western Pacific. The aim is to make surveillance aircraft, satellites and submarines work harder to find them, and to complicate any decision to intercept them. In the language of military planners, this is about denying an adversary a clear picture before a crisis, not only during one.

The logic is easy to understand, although its implications are disputed. Chinese officials describe the drills as routine preparation to defend sovereignty and sea lanes. Analysts in Washington, Tokyo and Canberra see rehearsals for a Taiwan contingency, in which Chinese forces would try to hold American reinforcements at a distance while keeping their own fleet intact. Others caution that exercises show intent and ambition, not proven skill, since coordinating scattered ships under surveillance is notoriously difficult.