The sentence or phrase conveys a tone of frustration:
"They have obstructed by every means Our peaceful commerce and finally resorted to a direct severance of economic relations, menacing gravely the existence of Our Empire."
Therefore they were stunned when the unthinkable happened Japanese planes bombed the U.S. fleet at Pearl Harbor on December 7, 1941. The following day, the United States declared war on Japan, and it soon entered into a military alliance with China.
On July 26, 1941, President Franklin Roosevelt seizes all Japanese assets in the United States in retaliation for the Japanese occupation of French Indo-China. On July 24, Tokyo decided to strengthen its position in terms of its invasion of China by moving through Southeast Asia.
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