When the representatives of 50 nations gathered in San Francisco four decades ago to create the United Nations, they invested the newly begotten global organization with the dreamiest hope of mankind: "To save succeeding generations from the scourge of war." Some 130 wars and more than 16 million fatalities later, the question is not whether the U.N. can fulfill its utopian promise--all too obviously it cannot--but what role, if any, it can play in the future.
The organization's continuing symbolic importance will be reaffirmed this week, when the largest gathering of world leaders in history--some 80 heads of state and government,...