LONDON (AP) -- Excitement about Barack Obama emerged as a global phenomenon Wednesday as commentators and citizens around the world welcomed the news that he had sealed the Democratic presidential nomination. The excitement was less about Obama's foreign policies -- which remain vague on many fronts -- than a sense that the candidacy of a black American with relatives in Africa and childhood friends in Asia marks a historic moment. Michael Cox, a professor of international relations at the London School of Economics, said Obama's win "has sent out a lot of positive signals around the world." "He has a...