China’s trade war with the rest of the world has unfolded through speedy expansion of a network of maritime choke points and deep water ports worldwide. Tariffs and unfair subsidies are part of that trade war, but the big story is about control of international shipping.

The United States, as the most powerful guarantor of freedom of the seas, tends to view China’s network of imperial maritime outposts as a Navy problem. But the Navy, especially in the Indian and Pacific oceans, is stretched dangerously thin, even with allies and partners.