As expected, the visit to the United States by China's leader-in-waiting, Xi Jinping, did not result in any policy breakthroughs. He is, after all, only the crown prince and has not yet been anointed No. 1.

The trip continued a practice begun 10 years ago when China's then vice president, Hu Jintao, was invited to Washington by his American counterpart, Dick Cheney, so that the U.S. could take the measure of the man scheduled to become China's leader.

On this visit there were strong echoes of the Hu trip a decade ago. In 2002, then Vice President Hu noted that it was a significant time because it was 30 years since Richard Nixon had made his historic visit to China in February 1972, a visit that Nixon claimed had changed the world.