The U.S. and China are headed for a showdown at sea. U.S. officials say that within days the U.S. military will conduct “freedom of navigation” patrols to challenge Beijing’s territorial claims in the South China Sea’s strategic Spratly archipelago. That area lies more than 700 miles off China’s coast, between Malaysia, the Philippines and Vietnam, but China’s government has warned that it is “seriously concerned” about U.S. action and “will absolutely not permit any country to infringe on China’s territorial waters.”
Now’s a good time, then, to clarify what’s going on. The U.S. and its Asian partners are trying to curb a Chinese campaign to conquer one of the world’s most vital international waterways. The South China Sea is home to rich natural resources and half of all global shipborne trade: some $5 trillion a year in oil, food, iPhones and more. By asserting “indisputable sovereignty” over its nearly 1.35 million square miles, including vast swaths of sea belonging to its neighbors, Beijing threatens to hold hostage—and to wage war over—the economic heart of East Asia.