United States territorial acquisitions
The Panama Canal Zone was an unorganized US territory located within the Republic of Panama. It was established under the Hay–Bunau-Varilla Treaty in 1903 and disestablished in 1979 under the Torrijos–Carter Treaties. Panama gained full control over the Panama Canal in 1999.
Harold Brown (Secretary of Defense)
Besides broad national security policy matters, Brown had to deal with several more immediate questions, among them the Panama Canal issue. Control of the Panama canal zone had been a source of contention ever since Panama achieved its independence from Colombia in 1903 and granted the United States a concession "in perpetuity".
In the mid-1960s, after serious disturbances in the zone, the United States and Panama began negotiations that went on intermittently until September 7, 1977, when the countries signed two treaties, one providing for full Panamanian control of the canal by the year 2000 and the other guaranteeing the canal's neutrality. The Defense Department played a major role in the Panama negotiations. Brown championed the treaties through a difficult fight to gain Senate approval (secured in March and April 1978), insisting that they were both advantageous to the United States and essential to the canal's future operation and security.