Sometimes a chance juxtaposition highlights an issue that needs to be addressed. One such popped up the other day in my International Herald Tribune. It published an obituary of Joseph Rotblat, a Warsaw-born nuclear physicist who made brief but important contributions to the creation of the atomic bomb at Los Alamos in 1944. An early advocate of the need for an Allied bomb to counter the one being worked on by the Germans, Rotblat quit the program 'terribly shocked' when he learned that work on the bomb was continuing even though it had been learned that the Germans had no such weapon, writes Karl Ludvigsen.