In one of the great comedic routines of all time, Abbott and Costello went round and round about a baseball player by the name of Who and which base he was on. As Chinese President Hu Jintao shows up to be feted in Washington this week, the question is not whether Who's on first, but whether Hu's becoming first - the leader of a nation on a trajectory not merely to rival the United States as a "peer competitor," but to supplant it as the world's only superpower? Unfortunately, the answer may be no laughing matter.