From 1964 to 1973, the U.S. dropped more than two million tons of ordnance on Laos during 580,000 bombing missions—equal to a planeload of bombs every 8 minutes, 24-hours a day, for 9 years – making Laos the most heavily bombed country per capita in history. The bombings were part of the U.S. Secret War in Laos to support the Royal Lao Government against the Pathet Lao and to interdict traffic along the Ho Chi Minh Trail. The bombings destroyed many villages and displaced hundreds of thousands of Lao civilians during the nine-year period.

Up to a third of the bombs dropped did not explode, leaving Laos contaminated with vast quantities of unexploded ordnance (UXO). Over 20,000 people have been killed or injured by UXO in Laos since the bombing ceased. The wounds of war are not only felt in Laos. When the Americans withdrew from Laos in 1973, hundreds of thousands of refugees fled the country, and many of them ultimately resettled in the United States.

Here are some other startling facts about the U.S. bombing of Laos and its tragic aftermath: