A map of explosive regret

The red dots indicate where the U.S. dropped bombs. There's a lot of red. 

You can never tell what will bubble up to the top of the Internet on any given day.

Foreign Policy blogs about current research into the U.S. bombing of Cambodia during the late 1960s and early '70s. The full paper by Taylor Owen is fascinating, but a 2006 article by Owen and Ben Kiernan sums up:

The still-incomplete database (it has several “dark” periods) reveals that from October 4, 1965, to August 15, 1973, the United States dropped far more ordnance on Cambodia than was previously believed: 2,756,941 tons’ worth, dropped in 230,516 sorties on 113,716 sites. Just over 10 percent of this bombing was indiscriminate, with 3,580 of the sites listed as having “unknown” targets and another 8,238 sites having no target listed at all.

That's enough to sprinkle 13 grams of high explosive over every square meter of Cambodia. Incidentally, that's about the recommended rate of ammonium nitrate application.

Is it plausible the United States could have better achieved long-term goals through development efforts rather than carpet bombing the eastern half of Cambodia?

The Cambodian bombing campaign had two unintended side effects that ultimately combined to produce the very domino effect that the Vietnam War was supposed to prevent. First, the bombing forced the Vietnamese Communists deeper and deeper into Cambodia, bringing them into greater contact with Khmer Rouge insurgents. Second, the bombs drove ordinary Cambodians into the arms of the Khmer Rouge, a group that seemed initially to have slim prospects of revolutionary success. Pol Pot himself described the Khmer Rouge during that period as “fewer than five thousand poorly armed guerrillas ... scattered across the Cambodian landscape, uncertain about their strategy, tactics, loyalty, and leaders.”

As the 37th anniversary of the fall of Phnom Penh approaches, it's worth remembering that the cities were evacuated on the pretext that the U.S. intended to bomb urban areas. As the city was full of people displaced by the war, what we now consider a flimsy excuse may have sounded quite plausible.

Also, what was worth bombing in Oddar Meanchey?