History of the Panama Canal
During World War II, the canal proved a vital part of the U.S. military strategy, allowing ships to transfer easily between the Atlantic and Pacific. Politically, the Canal remained a territory of the United States until 1977, when the Torrijos–Carter Treaties began the process of transferring territorial control of the Panama Canal Zone to Panama, a process completed on 31 December 1999.
Panama–United States relations
The United States first attempted to acquire control of a canal on the Panamanian isthmus via the Hay-Herran Treaty of 1903, but the treaty was not ratified. Desperate to construct a canal, the United States saw the separatist movement as an opportunity. Despite the Bidlack-Mallarino Treaty of 1846 in which the United States would intervene in the event of a disorder between Panama and Colombia in Colombia’s favor, the United States prevented Colombian forces from moving across the isthmus to stop the Panamanian uprising. On November 4, 1903, the immediate support of the USA secured the Declaration of Independence of Panama from Colombia. In return, Panama signed the Hay–Bunau-Varilla Treaty three weeks later, granting the USA sovereign rights over the interoceanic canal that would be built over the following decade.