In organizing their combined effort, the British and the Americans achieved an unprecedented degree of cooperation. The war effort in Britain was officially presided over by a reduced war cabinet, whereas Churchill assumed the major responsibility with the common consent of his colleagues who recognized his inexhaustable energy and his spirit of invention. The chiefs of staff formulated plans based on the Prime Minister's recommendations; then the Prime Minister took the final decision. Constitutionally the same system was followed in America, except that President Roosevelt had to pav greater attention to public opinion. Although Roosevelt and Churchill were very different in character they shared a common attitude towards the importance of their respective roles and duties. They cemented a close friendship which was never shaken bv differences of opinion. They communicated regularly with each other by cables between Washington and London. By this means decisions could be taken jointly. The combined chiefs of staff were set up in Washington to draft plans and execute decisions. Their common language did much to facilitate work and to enhance mutual understanding. Cooperation lasted until the end of the war. The British and the Americans did not always agree on strategy or on the future of the world. There were certainly squabbles, but they always managed to reach an agreement. The two heads of state spelled out their collective war aims in a formal document which was drawn up before the United States entered the war. It was called the Atlantic Charter. All the governments which fought against Germany approved its terms. The Charter affirmed the rights of individuals and the need for cooperation during and after the war. At a meeting at Casablanca in January 1943 Roosevelt and Churchill reached another very important decision concerning their enemies. Although they declared that they were not fighting against the people of Italy, Germany and Japan, but against their governments and their corrupt leaders, they decided, on Roosevelt's suggestion, that no peace would be negotiated unless the enemy acknowledged and conceded defeat in an 'unconditional surrender'. This formula closed the door to possible compromises, but it showed the enemy the energy and fierce resolution with which the Allies were fighting and it gave encouragement to people in occupied countries.