Clive Kandel Moments in History Germany Surrenders in the Ruins of Berlin 1945. When the Second World War began in 1939, the President of the United States (then a neutral power), Franklin D. Roosevelt, issued a request to the major belligerents to confine their air raids to military targets.The French and the British agreed to abide by the request, with the provision that this was "upon the understanding that these same rules of warfare will be scrupulously observed by all of their opponents". The United Kingdom had a policy of using aerial bombing only against military targets and against infrastructure such as ports and railways of direct military importance. While it was acknowledged that the aerial bombing of Germany would cause civilian casualties, the British government renounced the deliberate bombing of civilian property, outside combat zones, as a military tactic. This policy was abandoned on 15 May 1940, two days after the German air attack on Rotterdam, when the RAF was given permission to attack targets in the Ruhr, including oil plants and other civilian industrial targets that aided the German war effort, such as blast furnaces that at night were self illuminating. The first RAF raid on the interior of Germany took place on the night of 15 May -- 16 May. Between 1939 and 1942, the policy of bombing only targets of direct military significance was gradually abandoned in favour of "area bombing"—large-scale bombing of German cities to destroy housing and civilian infrastructure. Although killing German civilians was never an explicit policy, it was obvious that area bombing must lead to large-scale civilian casualties.[6] Following the fall of France in 1940, Britain had no other means of carrying the war to Germany and after the entry of the Soviet Union into the war in 1941, bombing Germany was the only contribution Britain could make to meet Joseph Stalin's demands for action to open up a second front. With the technology available at the time, the precision bombing of military targets was possible only by daylight (and it was difficult even then). Daylight bombing raids conducted by Bomber Command involved unacceptably high losses of British aircraft, and bombing by night led to far lower British losses, but was of necessity indiscriminate due to the difficulties of noctural navigation and bomb aiming. Up to the end of March 1945 there had been a total of 314 air raids on Berlin, with 85 of those coming in the last twelve months. Half of all houses were damaged and around a third uninhabitable, as much as 16 km² of the city was simply rubble. Estimates of the total number of dead in Berlin from air raids range from 20,000 to 50,000; current German studies suggest the lower figure is more likely. This compares to death tolls of between 25,000 and 35,000 in the single attack on Dresden on 14 February 1945, and the 40,000 killed at Hamburg in a single raid in 1943, with both the Hamburg and Dresden raids each having lower casualty totals than the March 9/10, 1945 Operation Meetinghouse single firebombing raid on Tokyo, causing the loss of 100,000 lives in the Japanese capital. The relatively low casualty figure in Berlin is partly the result of the city's distance from airfields in Britain, which made big raids difficult before the liberation of France in late 1944, but also a testament to its superior air defences and shelters.