Wikipedia
On 30 March 1942 Professor Frederick Lindemann, Baron Cherwell, the British government's chief scientific adviser, sent to the British Prime Minister Winston Churchill a memorandum which after it had become accepted by the Cabinet became known as the dehousing paper.
The paper was delivered during a debate within the British government about the most effective use of the nation's resources in waging war on Germany. Should the Royal Air Force (RAF) be reduced to allow more resources to go to the British Army and Royal Navy or should the strategic bombing option be followed and expanded? The paper argued that from the analysis of the reaction of the British population to the Blitz, the demolition of people's houses was the most effective way to affect their morale, even more effective than killing relatives. Given the known limits of the RAF in locating targets in Germany and providing the planned resources were made available to the RAF, destroying about thirty percent of the housing stock of Germany's fifty-eight largest towns was the most effective use of the aircraft of RAF Bomber Command, because it would break the spirit of the Germans. After a heated debate by the government's military and scientific advisers, the Cabinet chose the strategic bombing campaign over the other options available to them.