The signing of the Panama Canal Treaties on September 7, 1977, established a new relationship between the United States and the Republic of Panama and modified the procedures for operation and defense of the Panama Canal. It also presented a unique challenge to the U.S. military in Panama which had to adjust quickly to newly assigned missions brought about by the treaty and to the new working relationship all the while carrying out its other missions, including the defense and protection of the Panama Canal.

Initial treaty implementation planning

While that Treaty provided the general framework for this new relationship and ensuing responsibilities (and the U.S. Public Law passed by the U.S. Congress in September 1979 provided the authority), extensive planning under a compressed time period was required by the U.S. military community (the U.S. Southern Command and its component commands in coordination with the military services and many other agencies within the Department of Defense).

Such planning began immediately after the signing of the two Treaties because the Panama Canal Treaty had stipulated that both Treaties were to enter into force six months after the exchange between the two governments of the instruments of ratification of the Treaties. However, one of the conditions attached to the U.S. Senate's ratification of these Treaties (and agreed to by Panamanian Head of Government General Torrijos) in March and April 1978 established October 1, 1979, as the date of their implementation (commonly referred to as Treaty Day). (To preclude the appearance of prejudging Senate action on ratifying the two Treaties, initial Treaty Implementation planning was classified; much of it was declassified after the Senate ratified them in 1978.)

The Treaties' instruments of ratification were exchanged between President Carter and General Torrijos in Panama City on June 17, 1978, a visit which required considerable support by the U.S. military. (During his two days in Panama, President Carter spoke to the American community in a visit to Fort Clayton the day after having spoken to the Panamanian people gathered at the Fifth of May Plaza.)