The principles of Allied strategic doctrine in the event of Japan entering the war were established at a secret conference between 29 January 1941 and 27 March 1941 . The strategy set forth the principle of Europe first , with the Far East being a defensive war . After the attack on Pearl Harbor , the British prime minister , Winston Churchill , and the American president , Franklin D. Roosevelt , met at the First Washington Conference . This conference reaffirmed the doctrine of Europe first . At the third Washington Conference in May 1943 alleviating pressure on China was discussed , in particular through the Burma Campaign . At the Quebec Conference in August intensifying the war against Japan was decided and South East Asia Command reorganised . The Second Quebec Conference in September 1944 discussed the involvement of the British Navy against the Japanese
Second Quebec Conference
Second Quebec Conference
Japanese occupation of Malaya