NEW HAVEN – History’s turning points are rarely evident with great clarity. But the February 4 joint statement of Russian President Vladimir Putin and Chinese President Xi Jinping as the Winter Olympics opened in Beijing may be an exception — signaling a new turning point in a new Cold War. Triangulation was America’s decisive strategic gambit in the first Cold War. Richard Nixon’s rapprochement with China, 50 years ago this month, isolated the former Soviet Union at a time when its