With an overstretched military and economic vulnerability, America can be eclipsed by China in key ways It could simply be this year's edition of the morose introspection that sometimes accompanies autumn. But it could also be the case that the relatively short epoch of the United States as the world's sole superpower is drawing to a close. A U.N. Conference on Trade and Development report released last week indicated that China was the largest recipient of foreign direct investment in 2003, having overtaken the United States. In the past year, foreign investment in the United States had dropped by 53...