Operation Soberania

Operación Soberanía (Operation Sovereignty) was a planned Argentine military invasion of Chile started on 22 December 1978 due to the Beagle conflict dispute. The invasion was halted after a few hours and Argentine forces retreated from the conflict zone without a fight. Whether the Argentine infantry actually crossed the border into Chile has not been established. Argentine sources insist that they crossed the border.

In 1971 Chile and Argentina agreed to a binding arbitration of an international tribunal to settle a boundary dispute. On 22 May 1977 Queen Elizabeth II announced the judgment, which awarded the Picton, Nueva and Lennox islands to Chile.

On 25 January 1978 Argentina rejected the decision and attempted to militarily coerce Chile into negotiating a division of the islands that would produce a boundary consistent with Argentine claims.

According to Argentine sources, after the Argentine repudiation of the arbitration award in January 1978, the invasion plans were given different names depending on the planning level and phase. Also, the targets of the invasion changed according to the political situation and to the information about the Chilean defense effort: first only the Picton, Nueva and Lennox islands, then the "little" Evout, Hoorn, Deceit and Barnevelt islands, then both groups of islands. Finally, on Friday 15 December 1978 Argentina's President Jorge Videla signed the order to invade on 21 December 1978 at 04:30 as the beginning of the invasion, but it was postponed to the next day because of the bad weather conditions in the landing zone.

At the time of the crisis, the Argentine military was substantially larger than that of Chile; in addition, the Chilean regime was more politically isolated and had suffered deteriorating relations with its chief suppliers of arms. The Chilean military, however, had the advantage of defending difficult terrain, as well as being a more professional force. On the other hand, decades of intervention by the Argentine armed forces in day-to-day politics had degraded their professional skills.

There was considerable international condemnation of the Chilean regime's human rights record, with the United States expressing particular concern after Orlando Letelier's 1976 assassination in Washington D.C. The United States banned the export of weapons to Chile through the Kennedy Amendment, later International Security Assistance and Arms Export Control Act of 1976. 16 Northrop F-5's were delivered to Chile before the embargo took effect, but they arrived without any armament. In 1980 Chile was excluded from UNITAS joint naval maneuvers because of human rights violations.Germany,Austria and the United Kingdom the traditional supplier of the Chilean Armed Forces, did not supply weapons to Chile.

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Wikipedia