What major us territory created a major concern for japan as they entered wwii?

Before Pearl Harbor, the Japanese had already began imperial expansion in China (1937) and in other territories and islands. The Empire of Japan entered World War II in September 27, 1940, by signing the Tripartite Pact with Germany and Italy, though, it wasn't until the attack on Pearl Harbor on December 7, 1941, that the US entered the conflict.[1] Over the course of seven hours there were coordinated Japanese attacks on the U.S.-held Philippines, Guam and Wake Island and on the British Empire in Borneo, Malaya, Singapore, and Hong Kong.[2] The strategic goals of the offensive were to cripple the U.S. Pacific fleet, capture oil fields in the Dutch East Indies, and maintain their sphere of influence of China, East Asia, and also Korea. It was also to expand the outer reaches of the Japanese Empire to create a formidable defensive perimeter around newly acquired territory.[3]

Explanation:

They wanted Midway. I switched on accident

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Source:

Wikipedia

d: their own individual powers within the new goverment