Some knowledge of history and the memories of a long life have given me a sense of wonder at the shape-shifting habit of ideals and the ideologues who espouse them. What brings this to mind is the eloquent and idealistic foreign-policy speech that President Bush recently gave in London. Some commentators liken Bush's rhetoric to the idealism of Ronald Reagan, but it has earlier, Democratic antecedents, both in Woodrow Wilson's war "to make the world safe for democracy" and in FDR's "Four Freedoms." In both cases, these ideals were carried forward on American bayonets. Bush's London address was masterfully crafted...