It was a stifling hot July day in 1992 when Qian Qichen, China’s foreign minister, took a helicopter to the lakeside villa of Kim Il Sung, North Korea’s leader. Qian was used to uncomfortable situations — he had sparred with Brent Scowcroft three years earlier after the massacre at Tiananmen Square — but this trip was uniquely sensitive. Qian’s task was to deliver a message to Kim from his boss, Jiang Zemin, explaining that China had decided to establish diplomatic relations with South