In his final state of the nation speech Monday, Philippine President Rodrigo Duterte defended his refusal to confront China over Beijing's seizure and fortification of his country's islets in the South China Sea. "It will be a massacre if I go and fight a war now," said Duterte. "We are not yet a competent and able enemy of the other side." Duterte is a realist. He will not challenge China to retrieve his lost territories, as his country would be crushed. But Duterte has a hole card: a U.S. guarantee to fight China, should he stumble into war with China.