Democrats are counting on Sen. John Kerry's military credentials to convince voters that he can be trusted with America's national security. But documents that surfaced over the weekend raise serious questions about whether Kerry was duped in the 1990s into helping the Chinese military perfect its ability to strike the U.S. with nuclear weapons. In 1996 Kerry met with Liu Chaoying, the daughter of a powerful Chinese military official who also doubled as vice president of a subsidiary of the state-owned China Aerospace Corp. Before the meeting, held in Kerry's Senate office, Liu's sponsor, Johnny Chung, made clear she was...