Like wedding anniversaries, state visits by foreign leaders are occasions to celebrate the positive, and that’s what the Obama Administration will stress as Chinese President Xi Jinping tours the U.S. this week. Get ready for an announcement about arms-control in cyberspace, a progress report on a bilateral investment treaty, and bromides about mutual friendship.

These columns have rooted for China’s emergence as a major U.S. trading partner and responsible global power since Deng Xiaoping became the first Chinese Communist...