launched from a submarine-towed capsule. Background The British Area Bombing Directive issued on February 14, 1942, focused on undermining "the morale of the enemy civil population and in particular the industrial workers". According to British philosopher A. C. Grayling, Lübeck, with its timbered medieval buildings, was chosen because the Royal Air Force (RAF) Air Staff "were eager to experiment with a bombing technique using a high proportion of incendiaries" to help them carry out the directive. The RAF was aware of using a high proportion of incendiaries during bombing raids was effective because cities such as Coventry had been subject to such attacks by the Luftwaffe during the Blitz. New heavy bombers, improved navigation and bombing systems, and new tactics led to a devastating increase in the effectiveness of the RAF's bombing offensive on Germany, starting with the bombing of Lübeck in March 1942. A series of follow-up attacks using a similar pattern, was mounted against Rostock between April 24 and 27, 1942. The destruction of Lübeck and Rostock came as a profound shock to the German leadership and population. Adolf Hitler was enraged and on April 14, 1942, he ordered "that the air war against England be given a more aggressive stamp. Accordingly, when targets are being selected, preference is to be given to those where attacks are likely to have the greatest possible effect on civilian life. Besides raids on ports and industry, terror attacks of a retaliatory nature [Vergeltungsangriffe] are to be carried out on towns other than London". In April and May 1942, the Luftwaffe designed the Baedeker Raids on British cities with the hope of forcing the Royal Air Force to reduce their actions. The Luftwaffe continued to target cities for their cultural value for the next two years. The Baedeker-type raids ended in 1944 as the Germans realized they were ineffective; unsustainable losses were being suffered for no material gain. January 1944 saw a switch to London as the principal target for retaliation. On January 21, the Luftwaffe mounted Operation Steinbock, an all-out attack on London using all of its available bomber force in the west. This too was largely a failure and German efforts were redirected toward the ports the Germans suspected were going to be used for the Allied invasion of Germany. Operation Steinbock was the last large-scale bombing campaign against England using conventional aircraft; thenceforth only the V-1 flying bomb and