Thailand's royal succession is not going according to the junta's plan. When revered King Bhumibol Adulyadej died Oct. 13 after 70 years on the throne, he left behind a power vacuum that could shake the country to its core. Almost immediately after the king's death became public, the leader of the Thai junta, Gen. Prayuth Chan-ocha, announced that Crown Prince Maha Vajiralongkorn, whom the late king named as his heir in 1972, would take the throne. Despite the crown prince's unpopularity and scandalous reputation, his appointment came as a relief, ostensibly settling the contentious issue of royal succession after years of uncertainty helped to fuel the country's cyclical political unrest. But a few hours later, Prayuth stunned observers by revealing that the crown prince had allegedly requested time to mourn before taking the throne. In the meantime, the chief of Thailand's Privy Council, 96-year-old retired Gen. Prem Tinsulanonda, will serve...