Isn't it clear by now that the U.S. and its allies are not likely to be able to wipe out Al-Qaeda or ensure that the Americans are not attacked again domestically? As the British acknowledged in July, the London attacks were just a matter of when, not if. To be sure, the terrorists can't win this war, but neither can the Americans. The most serious risk is that Al-Qaeda will sooner or later be able to attack the U.S. with a biological or nuclear weapon, not merely the conventional bombs used in London and Madrid or the suicide car bombs...