However, the Chinese intervention did not stem the Japanese advance and by May 1942 the Japanese had occupied all of Burma, reaching the frontiers of India. Koo noted that the Japanese victories in southeast Asia were further cutting off China from the rest of the world, but at least had the benefit of making British officials more respectful as he noted after the fall of Singapore, the British lost their customary disdain for Asians. The way that only four divisions of the Imperial Japanese Army who despite being outnumbered three to one by an Anglo-Indian-Australian force opposing them had been able to conquer Malaya and Singapore, billed at the time as the "Gibraltar of the East", in less than two months both astonished and shocked British officials. Koo noted that through Churchill was firmly committed to the "Europe First" strategy that the Japanese victories in southeast Asia that had pushed the Imperial Japanese Army right to the frontiers of India increased the importance of keeping China in the war. From 1937 to 1945, 38 of the 51 divisions of the Imperial Japanese Army were fighting in China with only 9 divisions being used for the conquest of southeast Asia in late 1941-early 1942. In December 1941, the Japanese sent 1 division to conquer the British colony of Hong Kong; 4 divisions to conquer the British colonies of Malaya and Singapore; another 2 divisions to conquer the American colony of the Philippines; another 3 divisions to conquer the Dutch colony of the Netherlands East Indies (modern Indonesia); and finally assigned 2 divisions to the conquest of the British colony of Burma. The Special Landing Force of the Imperial Japanese Navy was assigned the task of taking Wake island and Guam. From the British perspective, it was crucial that the Chinese continued to fight the Japanese, which improved the Chinese bargaining position in London. Koo noted that paradoxically the Allied defeats in 1941-1942 had improved China's bargaining position as both the British and the Americans very much wanted to keep the Chinese fighting in order to keep the 38 Japanese divisions in China from being used against their forces. Koo also pressed hard to end the 19th century "unequal treaties" and especially wanted the end of British extraterritorial rights in China. On 11 January 1943, Koo signed in London a new Sino-British treaty that saw Britain renounce all of its extraterritorial rights