Nor is it any protection to have committed the treason abroad, a point established in the case of Tomoya Kawakita, a young Japanese-American who on the eve of war went to Japan to visit and was prevented by the outbreak of war from returning. During the war, the court noted, he reached his majority in Japan, changed his registration from American to Japanese, showed sympathy with Japan and hostility to the United States, served as a civilian employee of a private corporation producing war materials for Japan, and brutally abused American prisoners of war who were forced to work there. He was brought up on the treason charge when he returned to America on an American passport. In sustaining his conviction, the Supreme Court established that an American citizen owes allegiance to America wherever he may reside.