TOKYO (Reuters) -U.S. Defense Secretary Pete Hegseth described Japan on Sunday as indispensable for tackling Chinese aggression and said implementing of a plan to upgrade the U.S military command in the country would get under way. "We share a warrior ethos that defines our forces," Hegseth told Japanese Defence Minister Gen Nakatani at a meeting in Tokyo. "Japan is our indispensable partner in deterring communist Chinese military aggression," including across the Taiwan Strait, he said.