FOR years China has sought to divide and rule in the South China Sea. It worked hard to prevent the countries challenging it over some or all of its absurdly aggrandising territorial claims in the sea from ganging up against it. So when tensions with one rival claimant were high, it tended not to provoke others.

Not any more. In a kind of united-front policy in reverse, it now seems content to antagonise them all at the same time. This is both encouraging closer co-operation among neighbours and driving them closer to external powers including India, Australia, Japan and, above all, America.

The latest fight China has picked is with a country with which—unlike Brunei, Malaysia, the Philippines, Taiwan and Vietnam—it has no territorial dispute: Indonesia. On March 21st the chargé d’affaires at China’s embassy in Jakarta was hauled in to receive a stiff protest. A Chinese coastguard vessel had rammed free a Chinese fishing boat as it was towed into port after being caught allegedly fishing in Indonesian waters. The crew of eight was already in detention. In a similar incident three years ago, Indonesia released detained crew members when confronted by an armed “maritime law-enforcement” vessel belonging to China’s fisheries bureau.

http://www.economist.com/news/asia/21695565-sea-becomes-more-militarised-risks-conflict-grow-china-v-rest