In a few scant years the United States overturned George Washington's advice and the presumption of its history by entering what turned out to be a permanent alliance in Europe. Historians still argue, but at this distance NATO looks like a masterful act of statecraft, the right risk-averse choice even if it played some part in confirming Stalin's hostility and the division of Europe. The story has been told before, but Cook, a distinguished foreign correspondent, helps us think about whether existing arrangements are still the right choice. The chapters in the Sloan volume were background to a report of the North Atlantic Assembly, the group of NATO parliamentarians. There is no finer set of authors; they cover the range from defense burden to nuclear weapons to out-of-area issues, so called. Yet the theme of the assembly report-increasing NATO's European "pillar" so as to keep America fully engaged, even if deficits impel it to withdraw some troops-seems like yesterday's issue, and so is a reminder how fast events are moving in an area where change used to be glacial.