1952: The Treaty of San Francisco grants control of Okinawa to the United States. The U.S. sends its first shipment of chemical weapons to Okinawa for possible deployment in the 1950-53 Korean War.
1962-63: The U.S. sends further chemical-weapons shipments to Okinawa.
1969: A leak of chemical weapons at Chibana Ammunition Depot sickens 24 Americans. The U.S. government pledges to remove all stockpiles. Alleged sea-dumping of these materials is carried out near Okinawa. U.S. President Richard Nixon announces the end of chemical-weapons production and pledges to use existing stockpiles only in retaliation.
1971: In what was codenamed Operation Red Hat, Okinawa's chemical-weapons stockpile is shipped to Johnston Island in the North Pacific, which is under U.S. control.
1972: Okinawa reverts to Japanese control. The U.S. Congress bans sea-dumping of chemical weapons.
1977: The U.S. incinerates its stocks of Agent Orange near Johnston Island.
2000: The last load of U.S. chemical weapons taken from Okinawa to Johnston Island during Operation Red Hat is destroyed.