On September 7, 1977, Carter and Torrijos met in Washington to sign the treaties in a ceremony that also was attended by representatives of twenty-six other nations of the Western Hemisphere. The Panama Canal Treaty, the major document signed on September 7, abrogated the 1903 treaty and all other previous bilateral agreements concerning the canal. The treaty was to enter into force six months after the exchange of instruments of ratification and to expire at noon on December 31, 1999...

The second treaty, the Treaty Concerning the Permanent Neutrality and Operation of the Panama Canal, or simply the Neutrality Treaty, was a much shorter document. Because it had no fixed termination date, this treaty was the major source of controversy...

Notable among the Senate modifications of the Neutrality Treaty were two amendments incorporating the October 1977 Statement of Understanding, and interpreting the "expeditious" transit of United States and Panamanian warships in times of war as being preferential. Another modification, commonly known as the DeConcini Condition, stated that "if the Canal is closed, or its operations are interfered with [the United States and Panama shall each] have the right to take such steps as each deems necessary, ... including the use of military force in the Republic of Panama, to reopen the Canal or restore the operations of the Canal." Modifications of the Panama Canal Treaty included a reservation requiring statutory authorization for payments to Panama set forth in Article XIII and another stating that any action taken by the United States to secure accessibility to the Canal "shall not have as its purpose or be interpreted as a right of intervention in the internal affairs of the Republic of Panama or interference with its political independence or sovereign integrity." Reservations attached to both treaties made the United States provision of economic and military assistance, as detailed in the ancillary agreements attached to the treaties, nonobligatory.

The inclusion of these modifications, which were never ratified in Panama, was received there by a storm of protest. Torrijos expressed his concern in 2 letters, the first to Carter and another sent to 115 heads of state through their representatives at the UN. A series of student protests took place in front of the United States embassy. The DeConcini Condition was the major object of protest. Although the reservation to the Panama Canal Treaty was designed to mollify Panamanian fears that the DeConcini Condition marked a return to the United States gunboat diplomacy of the early twentieth century, this provision would expire in 2000, whereas the DeConcini Condition, because it was attached to the Neutrality Treaty, would remain in force permanently.

Despite his continuing concern with the ambiguity of the treaties with respect to the United States role in defense of the canal after 2000, the close Senate vote made Torrijos aware that he could not secure any further modification at that time. On June 16, 1978, he and Carter signed the instruments of ratification of each treaty in a ceremony in Panama City. Nevertheless, Torrijos added the following statement to both Panamanian instruments: "The Republic of Panama will reject, in unity and with decisiveness and firmness, any attempt by any country to intervene in its internal or external affairs." The instruments of ratification became effective on June 1, 1979, and the treaties entered into force on October 1, 1979.

...relations between the government [of Panama] and student groups began to deteriorate in 1976, and a variety of competing student federations developed, notably the Federation of Revolutionary Students (Federación de Estudiantes Revolucionarios-- FER), a group on the far left. Student groups were leaders in the opposition to ratification of the Panama Canal treaties, objecting largely to the continued presence of United States military bases in Panama.