"As one Laotian said, the bombs fell like rain," President Barack Obama said in a visit to Laos earlier this month. "I realize that having a US president in Laos would've once been unimaginable. Six decades ago, this country fell into civil war, and as the fighting raged next door in Vietnam, your neighbors and foreign powers, including the United States, intervened here. As a result of that conflict and its aftermath, many people fled or were driven from their homes."

For the first time, an American president admitted that his country dropped those bombs, and as a result innocent people became refugees. Obama didn't apologize. But he explained why the US made bombs rain from the sky — more bombs than the US dropped on Germany and Japan during World War II.

"At the time the US government did not acknowledge America's role," Obama said. "It was a secret war. And for years the American people did not know. Even now, many Americans are not aware of this chapter in our history and it's important that we remember it today."