Following the Japanese attack on Pearl Harbor and against several other countries on December 7–8, 1941, the United States, United Kingdom, and other Allies declared war. The Second Sino-Japanese War became part of the global conflict of World War II. Japanese forces initially experienced great success against Allied forces in the Pacific and Southeast Asia, capturing Thailand, Hong Kong, Malaya, Singapore, the Dutch East Indies, the Philippines, and many Pacific Islands. They also undertook major offensives in Burma and launched air and naval attacks against Australia. The Allies turned the tide of war at sea in mid-1942, at the Battle of Midway. Japanese land forces continued to advance in the New Guinea and Solomon Islands campaigns but suffered significant defeats or were forced to retreat at the battles of Milne Bay, the Kokoda Track, and Guadalcanal. The Burma campaign turned, as the Japanese forces suffered catastrophic losses at Imphal and Kohima, leading to the greatest defeat in Japanese history up to that point.