Area bombing directive The Area Bombing Directive was a directive from the wartime British Government ' s Air Ministry to the Royal Air Force which ordered RAF bombers to attack the German industrial workforce and the morale of the German populace through bombing German cities and their civilian inhabitants . Background and implementation . The " Area Bombing Directive " ( General Directive No . 5 ( S . 46368 / 111 . D . C . A . S ) was a 14 February 1942 amendment to General Directive No . 4 ( S . 46368 D . C . A . S ) , issued by the British Air Ministry on 5 February 1942 , that had informed RAF Bomber Command that it had " Priority over all other commitments " , and directed RAF Bomber Command to bomb factories in occupied France . General Directive Number 5 amended Number 4 to make targets in Germany the priority for RAF Bomber Command . The directive issued on 14 February ( S . 46368 / 111 . D . C . A . S ) listed the primary industrial areas that were within 350 miles from RAF Mildenhall ; the distance being a little over the maximum range of the GEE radio navigation aid ( referred to in the directive as " T . R . 1335 " ) . The directive specifically mentions the Ruhr and that Essen , in the centre of the conurbation was to be given the dubious honour as the first target that was to be bombed ( the first attack on Essen under this directive was carried out on the night of 8 / 9 March ) . The objective of the directive was " To focus attacks on the morale of the enemy civil population and in particular the industrial workers . In the case of Berlin harassing attacks to maintain fear of raids and to impose A . R . P . measures " . The directive issued on 14 February listed the north coast industrial areas ( within range of GEE ) and industrial areas beyond the operational reach of GEE ( Berlin by name and northern central and southern Germany ) , as secondary targets to be bombed when the weather over those targets was more suitable for bombing than over the primary area . Other German cities mentioned by name and to be attacked with a high - explosives were Duisburg , Düsseldorf and Cologne . Billancourt in occupied France , that was the primary target in the directive issued on 5 February ( Air Ministry Reference 46268 D . C . A . S ) and immediately preceding this one , was to become secondary target ( it was bombed on the night 3 / 4 March ) . In addition the RAF were also directed to carry out specific operations to support Combined Operations , such as the periodic bombardment of targets of immediate strategic importance , for example naval units ( see Channel Dash that happened only 2 days before this directive was issued ) , but it added a qualifier that these were only to be carried out if good opportunities to attack primary targets were not missed . The directive issued on 14 February also stated that " You are accordingly authorized to employ your forces without restriction " which lifted the injunction placed on Bomber Command on 13 November 1941 ordering it to conserve its forces after the very heavy mauling it had suffered at the hands of Luftwaffe night fighters earlier that month . The day after the directive was issued ( on 15 February ) , the Chief of the Air Staff Charles Portal sought clarification from the Deputy Chief of Air Staff Air Vice Marshal Norman Bottomley who had drafted it : " ref the new bombing directive : I suppose it is clear the aiming points will be the built up areas , and not , for instance , the dockyards or aircraft factories where these are mentioned in Appendix A . This must be made quite clear if it is not already understood . " The first major target attacked in the campaign initiated by the directive was Essen on the night of 8 / 9 March 1942 . This was followed by repeated incendiary attacks on Essen and the other three large cities in the Ruhr , and then " as opportunity offered , fourteen other industrial cities in Northern , Central and Southern Germany . " Between 21 March and 3 September 1942 eight further modifications were made to the directive ( all under the same Air Ministry reference , but modified file references ) . These were : The operations of the RAF were also modified by other directives issued by the Air Ministry while Directive S . 46368 was still effective . For example , on 30 July 1942 ( S . 3319 A . C . A . S . Ops ) gave priority to " Transportation and Transformer Stations " for Number 2 Group and S . O . E . squadron . while on 4 September ( S . 46344 A . C . A . S . Ops ) directed that incendiary bombs were to be " dropped in harvest season during normal bombing operations " as cover for sabotage operations . On 14 January 1943 directive ( S . 46239 / ? ? A . C . A . S . Ops ) gave priority to attacking U - boat pen s of Lorient , St Nazaire , Brest and La Pallice on the western French coast . In line with the bombing of Genoa and Turin on 23 October 1942 and a speech by the British Prime Minister Winston Churchill six days later , warning the Italian government that the RAF would continue bombing Italian cities while Italy remained an Axis power , a directive was issued on 17 January 1943 ( S . 46368 / ? ? ? D . C . A . S . Ops ) added to the bombing list of targets the Industrial centres of Northern Italy — Milan , Turin , Genoa and Spezia . The Area Bombing Directive was superseded by the Casablanca directive ( C . S . 16536 S . 46368 A . C . A . S . Ops ) . It was approved by the Combined Chiefs of Staff at their 65th meeting on 21 January 1943 and issued by the British and United States Army Air Force Commanders on 4 February 1943 . The primary objective was " The progressive destruction and dislocation of the German military , industrial and economic systems and the undermining of the morale of the German people to a point where their capacity for armed resistance is fatally weakened . Every opportunity to be taken to attack Germany by day to destroy objectives that are unsuitable for night attack , to sustain continuous pressure on German morale , to impose heavy losses on German day fighter force , and to conserve German fighter strength away from the Russian and Mediterranean theatres of war . A list of target systems was also drawn up which gave priority to ( a ) Submarine construction yards , ( b ) German aircraft industry , ( c ) transportation , ( d ) oil plants ( e ) other targets in enemy war industry . The priority was to be varied with the strategic situation and the u - boat bases in France .