VIENTIANE, Laos — Declaring a “moral obligation” to heal the wounds of a secret war, President Obama on Tuesday pledged help to clear away the 80 million unexploded bombs the U.S. dropped on Laos a generation ago – more than 10 for every one of the country’s 7 million people.

Half a century ago, the United States turned Laos into history’s most heavily bombed country, raining down some two million tons of ordnance in a covert, nine-year chapter of the Vietnam War. Obama the first president to set foot in Laos while in office, lamented that many Americans remain unaware of the “painful legacy” left behind by a bombardment that claims lives and limbs to this day.

“The remnants of war continue to shatter lives here in Laos,” Obama said before an audience of students, businessmen and orange-robed Buddhist monks who held up cellphones to snap photos of the American president. “Even as we continue to deal with the past, our new partnership is focused on the future,” he said.

To that end, Obama announced the U.S. would double its spending on bomb-clearing efforts to $90 million over three years – a relatively small sum for the U.S. but a significant investment for a small country in one of the poorer corners of the world. Obama plans to put a human face on the issue when he meets Wednesday in Vientiane with survivors of bombs that America dropped.

The president did not come to apologize. Instead, he called the conflict a reminder that “whatever the cause, whatever our intentions, war inflicts a terrible toll – especially on innocent men, women and children.”

Thanks to global cleanup efforts, casualties from tennis ball-sized “bombies” that still litter the Laotian countryside have plummeted from hundreds to dozens per year. But aid groups say far more help is needed. Of all the provinces in landlocked Laos, only one has a comprehensive system to care for bomb survivors.

“We’re incredibly proud of the progress the sector has made over the last five years in terms of the decline in casualties and new victims,” said Channapha Khamvongsa of the nonprofit Legacies of War. “But we are concerned about the upwards of 15,000 survivors around the country that are still in need of support.”

The $90 million to clean up bombs joins another $100 million the U.S. has committed in the past 20 years. The Lao government, meanwhile, says it will boost efforts to recover remains and account for Americans missing since the war.

The punishing air campaign on Laos was an effort to cut off communist forces in neighboring Vietnam. American warplanes dropped more explosives on this Southeast Asian nation than on Germany and Japan combined in World War II.