For years, Americans told ourselves a comforting story about China: We invent, they copy us. That story is badly out of date. China is no longer just the world’s factory. In many technologies that will define the next decade, it is rapidly becoming the world’s laboratory, and U.S. companies now have much to learn from China. But here is the trap: Just as we may need more access to China’s best technology, Beijing is tightening the legal net around it. As former Google boss Eric S