The Asian order is under strain as China has become an economic colossus with growing military might and diplomatic influence. China is asserting territorial claims once considered impractical or worthless. Opposing China are Brunei, Japan, Malaysia, Philippines and Vietnam.
Washington is not a claimant, but has sparred with China over the U.S. Navy's legal right to engage in intelligence gathering within China's 200-mile exclusive economic zone. More important, America has a formal military alliance with Japan which, the president declared, covers disputed territories. Washington's military relationship with Manila is looser, but Philippine officials are seeking a similar territorial guarantee.
The Obama administration has escalated U.S. involvement by sending American aircraft over islands reclaimed by China and discussing joint patrols with Japanese aircraft. An aerial or maritime incident could result in a dangerous confrontation.