 With the start of the World War II in the Pacific, seeing an opportunity for Vietnam to challenge French colonization, he attempted to persuade the Japanese forces to declare independence for Vietnam in 1942 but was ignored.Diệm also tried to establish relationships with Japanese diplomats, army officers, and intelligence operatives who supported Vietnam's independence.In 1943, Diệm's Japanese friends helped him to contact Prince Cường Để, an anti-colonial activist, who was in exile in Japan.