During the Second Sino-Japanese War in 1937, Japan's military invaded central China. Also, in 1938-1939 Japan made an attempt to seize the territory of Soviet Russia and Mongolia, but suffered a serious defeats (see Battle of Lake Khasan, Battles of Khalkhin Gol). By now, relations with the Allied powers were at the bottom, and an international boycott against Japan to deprive it of natural resources was enforced. Thus a military move to gain access to them was needed, and so Japan attacked Pearl Harbor, bringing the United States to World War II. Using its superior technological advances in naval aviation and its modern doctrines of amphibious and naval warfare, Japan achieved one of the fastest maritime expansions in history. By 1942 Japan had conquered much of East Asia and the Pacific, including the east of China, Hong Kong, Thailand, Vietnam, Cambodia, Burma (Myanmar), Malaysia, the Philippines, Indonesia, part of New Guinea and many islands of the Pacific Ocean. Just as Japan's late industrialization success and victory against the Russian Empire was seen as an example among underdeveloped Asia-Pacific nations, the Japanese took advantage of this and promoted among its conquered the goal to jointly create an anti-European "Greater East Asia Co-Prosperity Sphere". This plan helped the Japanese gain support from native populations during its conquests, especially in Indonesia. However, the United States had a vastly stronger military and industrial base and defeated Japan, stripping it of conquests and returning its settlers back to Japan.