The is the ambassador from the United States of America to Japan. History Since the opening of Japan by Commodore Matthew C. Perry, in 1854, the U.S. has maintained diplomatic relations with Japan, except for the ten-year period between the attack on Pearl Harbor in 1941 (and the subsequent declaration of war on Japan by the United States) and the signing of the Treaty of San Francisco, which normalized relations between the United States and Japan. The United States maintains an embassy in Tokyo, with consulates-general in Osaka, Nagoya, Sapporo, Fukuoka, and Naha. Due to the significance of the relations between the two countries in recent years on trade and defense, with Japan being described by the United States State Department as "the cornerstone of the U.S. security interests in Asia," the post has been held by many significant American politicians, including Mike Mansfield, Walter Mondale, Tom Foley and Howard Baker. List of chiefs of mission The following is a list of chiefs of mission. Resident ministers Envoys extraordinary and ministers plenipotentiary Ambassadors extraordinary and plenipotentiary Notes See also Ambassadors of the United States Japanese Ambassador to the United States Embassy of the United States in Tokyo Embassy of Japan in Washington, D.C. Foreign relations of the United States Foreign relations of Japan Japan–United States relations Convention of Kanagawa Treaty of Amity and Commerce (United States–Japan) Security Treaty Between the United States and Japan Treaty of San Francisco Treaty of Mutual Cooperation and Security between the United States and Japan United States Forces Japan U.S.–Japan Status of Forces Agreement References U.S. ambassador a role most vital United States Department of State: Background notes on Japan External links United States Department of State: Chiefs of Mission for Japan United States Department of State: Japan United States Embassy in Tokyo Japan United States