In March 1945, only six weeks before his death, U.S. President Franklin D. Roosevelt delivered an address to Congress in which he announced plans for the creation of "a universal organization," a "permanent structure of peace." That organization was the United Nations, whose Charter called for saving the world "from the scourge of war" and for promoting "justice," "social progress," and "better standards of life in larger freedom." In subsequent decades, the United Nations did an effective job of encouraging human rights and social progress, but -- thanks largely to the behavior of the "great powers" -- proved less effective in preventing military aggression and war. Even so, public pressure for a peaceful world has secured important victories in the past, and the books are not closed on the future.