TOKYO—China’s slowing economy is highlighting the dependence of Japan on its giant neighbor, driving Tokyo’s business leaders to take a gentler line than the U.S. in trade conflicts.

“It is impossible for Japan to exist if we turn [China] into an enemy,” said Hiroaki Nakanishi, chairman of Hitachi Ltd. and the head of the nation’s top business federation, in an interview. “Maybe they can do that in America, but it doesn’t work like that in Japan.”

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