WASHINGTON — South Korea’s political turmoil is deepening since its martial law debacle, and analysts say China may have an opportunity to increase its leverage over the country. The current political chaos in Seoul is “working to[ward] Beijing’s advantage,” said Evans Revere, who served as the acting assistant secretary of state for East Asia and Pacific Affairs during the George W. Bush administration. “China, with its authoritarian approach to governing, is beneficiary” and “no doubt pleased because China sees the ascendancy of the Democratic Party, known for its sympathetic approach to the PRC, as a positive development,” Revere said. China’s