What began at a high school flagpole spread through Panama City within hours. The U.S. Army's 193rd Infantry Brigade deployed at 8:35 p.m. American-owned businesses were set ablaze. The Pan Am building, despite housing an American corporation, was Panamanian-owned -- but the fire gutted it anyway, and six bodies were found in the wreckage the next morning. Word traveled by radio, television, and telephone to the country's north coast, where the city of Colon erupted in fighting near the Canal Zone border at Cristobal. Incomplete censorship fed wild rumors on both sides, including a false American claim that the Canal Zone had been renamed the "United States Canal Zone" and would become an outright U.S. possession. The violence was not orchestrated -- the country's communists, some reporters' conspiracies notwithstanding, were caught off guard and commanded only a tiny fraction of those who took to the streets.

Ascanio Arosemena was nineteen years old. Witnesses say he was helping evacuate wounded protesters when he was shot from behind, through the shoulder and thorax. A photograph, said to have been taken shortly before his death, shows him supporting an injured man. He became the first of Panama's martyrs. The youngest was Maritza Avila Alabarca, a six-month-old girl who died of respiratory failure after her neighborhood was saturated with CS tear gas. Twenty-one Panamanians are memorialized at the former Balboa High School, each name inscribed on a column surrounding an eternal flame. Three or four Americans also died -- Staff Sergeant Luis Jimenez Cruz, Private David Haupt, and First Sergeant Gerald Aubin were killed by sniper fire in Colon. Santo Tomas Hospital treated 324 injuries. DENI investigators later found over 600 bullets embedded in the Legislative Palace alone. Declassified U.S. Army documents recorded 7,193 tear gas grenades fired, 460 pounds of chemical agents deployed, and thousands of rounds of ammunition expended.

International reaction ran sharply against the United States. Britain and France, long criticized by Washington for their colonial policies, accused America of hypocrisy. Egypt's Nasser suggested Panama nationalize the canal, as Egypt had done with Suez. Venezuela led a chorus of Latin American condemnation. The Organization of American States, on Brazil's motion, took jurisdiction from the UN Security Council and sent investigators, who accused the Americans of using unnecessary force. President Roberto Chiari broke diplomatic relations with the United States on January 10 and declared Panama would not resume them until Washington agreed to negotiate a new canal treaty. For this stand, Panamanians remember him as "the president of dignity." Amid the crisis, there were also quieter acts of conscience: many Panamanians sheltered American families who were endangered in Panama City, even as their own neighborhoods burned.

The events of January 9, 1964, are now recognized as the catalyst that ended American control of the Canal Zone. On April 3, 1964, both countries resumed diplomatic relations, and the United States agreed to work toward eliminating the causes of conflict. Thirteen years later, the Torrijos-Carter Treaties dissolved the Zone, set a timetable for closing U.S. military bases, and transferred full control of the Panama Canal to Panama at noon on December 31, 1999. Two monuments stand in Panama City today. One, at the former Balboa High School, surrounds an eternal flame with columns bearing the names of the dead. The other, in front of the Legislative Assembly, depicts three figures climbing a lamppost to raise the Panamanian flag -- a scene captured in a photograph that appeared on the cover of Life magazine. Every January 9, Panama honors its Martyrs' Day, a national holiday. The students who walked to that flagpole did not set out to change history. They set out to raise their flag.