Originally called Operation Blue Spoon, Operation Just Cause was an American military intervention to depose Panamanian dictator General Manuel Noriega and set up a democratic government. Just Cause was the end result of over two years of fruitless negotiations and escalations in tension between the U.S. government and Noriega’s regime.

Manuel Noriega actually started out with a close relationship with the U.S. government. He had been a paid CIA informant and was on the United States Army's payroll from 1955 to 1986. Noriega rose to power in Panama in 1983 as the Commander of the Panama Defense Force (PDF). Noriega employed several puppet presidents, but all the power rested solely with him. The relationship between Panama and the United States began to deteriorate when accusations of illegal acts began to surface in the early 1980’s. In 1988, the U.S officially indicted Noriega on drug trafficking and racketeering charges. Relations with the U.S. further soured when Noriega annulled Panama's presidential election in May 1989, declared himself head of state, and a U.S. marine was killed by Panamanian troops. The last straw was Noriega’s declaration of war upon the United States.

President George Bush Sr. ordered the invasion of Panama in December 1989, dubbed Operation Just Cause, which was initiated in the dark early morning hours of December 20. Operation Just Cause quickly attained results, with most of the heavy fighting over within the first 24 hours of conflict. After special forces cleared the way, approximately 24,000 U.S. troops seized control of Panama City. Sporadic sniper engagements followed for the next few days, but insurgents were quickly ferreted out. U.S. losses in Just Cause were extremely low with 2 killed and 34 wounded.

On December 24, Noriega fled to the Vatican’s embassy in Panama City. Negations with the Vatican to ensure Noriega’s hand-over quickly began, and U.S. soldiers surrounded the embassy. To persuade Noriega to come out, U.S. forces directed bright search lights and incredibly loud music at the building 24 hours a day. On January 3, 1990, Noriega surrendered himself to U.S. custody and was transported to Miami for trial. Manuel Noriega was convicted of drug trafficking, money laundering, and racketeering in 1992 and sentenced to 40 years in prison.

With order restored in Panama and Noriega’s regime toppled, Operation Just Cause was declared a success and American troop withdrawals began on December 27, continuing into January of 1990. Guillermo Endara, who probably would have won the suppressed election, was installed as president.