One of Asia's most opaque and intractable insurgencies may be expanding. Over the past week, Thai police have begun asserting that southern rebels were responsible for a string of bombings and arson attacks that occurred on Aug. 11-12, the birthday of Thailand's venerated queen and the country's Mother's Day. Separatist militants in the country's southernmost provinces, a Malay-speaking, predominantly Muslim region known historically as Patani, have been waging an insurrection against the state for more than two centuries. Though the insurgency has killed thousands of people -- more than 6,000 since 2004, when violence resurged after a two-decade lull -- it has generally been confined to the deep south. The recent attacks, however, targeted tourist hot spots across eight Thai provinces far north of where the separatists typically operate.
The military government, which has staked its legitimacy in part on restoring law and order to the country, continues to downplay any...
