Panama Canal - Defending the Canal

The military's presence in the Panama area dates back to before the United States constructed the canal, when it protected U.S. merchant trade lanes. Even during construction, the military supplied engineers, labor, and security. Fortification of the Canal Zone was only partially completed by 1913. The Hay-Buana-Varilla Treaty gave the United States the right to fortify the zone, but it was not until 1911 that Congress appropriated the funds to begin fortification construction. With Sydney Williamson as construction supervisor and Army engineer Major Eben E. Wilson the design engineer, construction began that year on three forts on the Atlantic side and two on the Pacific. In 1912 the Chief of Engineers organized a section in his office under Goethal's son, Army engineer Lieutenant George R. Goethals, to oversee fortification construction in the Canal Zone. The first Atlantic fort was operational in 1914 and the first on the Pacific side in 1916. By the time the United States entered World War I, there were nine operational forts at each end of the canal.

In 1917 the United States hastily acquired the Danish Virgin Islands, to counter a possible wartime flaw in the canal's defenses, ensuring they were not obtained by imperial Germany. Base rights in Trinidad were an important element of the Lend-Lease destroyer deal with the UK in 1940, the justification for these facilities being coverage of the southern routes through the Caribbean islands toward the Panama Canal. Also during World War II the United States was watchful of Martinique and Guadeloupe when these French West Indies islands in the were in under Vichy control. The US was prepared to seize them by force if need be to preclude their use by hostile forces.

During the 1930's, events and technological developments began to challenge the old axioms on which the defense of the Canal had been based. A crippling attack aimed at the locks and dams, and delivered either by an act of sabotage or by naval bombardment, had always been considered the only real danger to be guarded against. The possibility of hostile forces establishing a beachhead and moving overland to the Canal was not entirely discounted, but the absence of suitable landing places on the Atlantic side and the thick jungle of the Pacific lowlands were counted on to discourage any attack of this sort. The Army had disposed its defenses accordingly.

During the 1930's new instruments for delivering an attack emerged in the shape of the naval aircraft carrier and long-range bomber. Potential air bases from which an attack against the Canal might be launched came into being as a result of the growth of commercial aviation in South and Central America. Experience in jungle maneuvers was beginning to make a myth of the impenetrability of tropical forests. Finally, the Army's ability to move outside the Canal Zone and take defensive measures within the territory of the Republic of Panama was sharply curtailed by the changing relationship between the two countries. Although sabotage remained the most likely danger, air strikes by either land-based or carrier-based planes came to be regarded as the most serious threat because of the wider holes in the defense against them.

Plans for protecting the Canal against sabotage during an international crisis of this sort had been drawn up in Panama and given constant study ever since the spring of 1936. In 1939, These measures were instituted between 26 August 1939, when the President gave the signal to go ahead, and 01 September 1939. Three basic measures had been provided for: first, the installation and operation of special equipment in the lock chambers, designed to detect underwater mines and bombs and to prevent damage from this cause; second, the restriction of commercial traffic to one side of the dual locks; and third, the inspection of all ships before they entered the Canal and the placing of an armed guard on vessels while in transit through it.

Soon photography of Canal installations was banned for the duration of the war, mines were placed at both entrances to the Canal, low-altitude barrage balloons were placed over the locks with anti-submarine and torpedo nets placed in front of the locks, and chemical smoke pots were positioned throughout a 60 square mile area. The massive guns and batteries on military installations at either end of the Canal were prepared for use. The 6 to 16 inch (in.) guns were housed in 11 Atlantic and 12 Pacific batteries, and had a range up to 25 miles. To protect against air attack, anti-aircraft batteries were put in place across the Zone and two antiaircraft detachments were sent in September 1939. Two long-range radar stations were also established in the autumn of 1939.

Immediately after the Japanese attack on Pearl Harbor, the War Department instructed its department commanders to put the Rainbow 5 plan into effect. This was the Orange Plan, which identified the Japanese as the primary aggressor, and singled out the Panama Canal as one of the key defense initiatives.

By the time the build-up was complete, defenses consisted of nine airbases and airdromes, 10 ground forces posts, 30 aircraft warning stations, and 634 searchlights, antiaircraft gun positions and miscellaneous tactical and logistical installations. Twelve outlying airbases were also constructed in Peru, Ecuador, Guatemala, Nicaragua, and Costa Rica. An outer defense parameter of 960 nautical miles from the Canal was established and patrolled by air and sea.

When the United States found itself enmeshed in a two ocean war, the Panama Canal suddenly became the most strategic point on the globe. The convergence of naval and merchant fleet traffic at this point offered German U-boats a vital and tempting target. As a result, it became necessary to ring the canal's ocean approaches with protective bases. Agreements with the governments of Caribbean, Central American, and South American countries made it possible to secure sites for new bases throughout the area. The Lend Lease Agreement, consummated with Great Britain in September of 1940, yielded still other possible bases in this crucial locale. Not only were new base sites rapidly acquired, but United States bases already in existence were enlarged. Under the Greenslade Program of 1940, the three pre-1939 naval installations located in Puerto Rico, Cuba, and the Panama Canal Zone were all expanded.

Overriding the desire of the United States War Department to hold most of the bases for an indefinite period, the Department of State took cognizance of growing nationalist dissatisfaction and in December 1946 proposed a twenty-year extension of the leases on thirteen facilities. When the Panamanian National Assembly met in 1947 to consider ratification, a mob of 10,000 Panamanians armed with stones, machetes, and guns expressed opposition. Under these circumstances the deputies voted unanimously to reject the treaty. The incident was the first in which United States intentions were thwarted by a massive expression of Panamanian rage. By 1948 the United States had evacuated all occupied bases and sites outside the Canal Zone. During and after the Cold War, the U.S. military's Southern Command, headquartered in Panama, oversaw components of the Air Force, Army, Marine Corps, and Navy stationed there. Its mission was to assist Panama in defending the canal, command U.S. joint operations, promote democracy and cooperation throughout the Western Hemisphere, and support the U.S. drug control strategy. The Air Force, Army, Marine Corps, and Navy components occupied 5,420 buildings in an area of 36,000 hectares with functional utilities and infrastructure (roads, airstrips, and port areas). The permanently assigned military strength of the Southern Command in Panama numbered 8,500. In October 1997, the Southern Command headquarters relocated to Miami, FL, as part of the military pullout from Panama (U.S. Department of Defense). By the end of 1999, all remaining military installations, facilities, and land reverted to the Republic of Panama.

As part of the canal treaties, the U.S. military no longer maintains installations or a troop force in Panama after Dec. 31, 1999.

Under the Treaty Concerning the Permanent Neutrality and Operation of the Panama Canal [the Neutrality Treaty], the United States and Panama agreed to guarantee the canal's neutrality "in order that both in time of peace and in time of war it shall remain secure and open to peaceful transit by the vessels of all nations on terms of entire equality." In times of war, however, United States and Panamanian warships were entitled to "expeditious" transit of the canal under the provisions of Article VI. President Torrijos of Panama was so concerned with the ambiguity of the Neutrality Treaty, because of Panamanian sensitivity to the question of United States military intervention, that, at his urging, he and President Carter signed the Statement of Understanding on October 14, 1977, to clarify the meaning of the permanent United States rights. This statement, most of which was subsequently included as an amendment to the Neutrality Treaty and incorporated into its instrument of ratification, included a declaration that the United States "right to act against any aggression or threat directed against the Canal . . . does not mean, nor shall it be interpreted as the right of intervention of the United States in the internal affairs of Panama."

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 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."

The DeConcini Condition was the major object of protest in Panama. 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.

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