It’s time to bring the pain. South Korea’s jittery after its northern neighbor conducted a fourth nuclear test last week, claiming it was a hydrogen bomb. Seoul is hoping the U.N. and China can chasten North Korea with crippling sanctions. On Tuesday, U.S. lawmakers overwhelmingly voted in favor of similar measures, while an undeterred Kim Jong Un called for beefing up the country’s nuclear arsenal. But South Korea, which shot down a northern drone today, is betting that China, as one of Pyongyang’s only friends, will stop talking softly and use its big stick.