At 7:30AM on March 16, 1968, a shallow trench in My Lai, Vietnam began filling with the bodies of local men, women, and children who had been systematically slaughtered at the hands of U.S. forces. When the extermination was complete, nearly 600 corpses had been unceremoniously tossed in the mass grave.

A young Army colonel by the name of Colin Powell headed an Army investigation team that eventually brought charges against a remorseless Lt. William F. Calley for the atrocities committed. No one else spent a day in prison for the massacre. A young Seymour Hersch, who many years later broke the story of abuse at Abu Ghraib prison in Iraq, was the first reporter to get inside the story of My Lai, and it won him a Pulitzer prize.

Just as importantly, the story of My Lai helped to solidify a growing, but loose, coalition of anti-war groups into a much stronger movement to end America’s involvement in the Vietnam war. The thing is, without the reporting of Hersch, and the dogged persistence of a journalist-turned-soldier (via the draft) Rod Ridenhour, we might never have learned about the atrocities.

Years later, Ridenhour recounted:

The important thing is, this was an act of policy, not an individual aberration. My Lai didn’t happen because Lieutenant Calley went berserk. There were similar acts of policy all over the country…

His words could just as easily be describing the situation in Iraq over the past five years. At some point in the future, I think Americans are going to be absolutely shocked by some of the revelations that trickle out of Iraq. I don’t know why they should be shocked. If the photos and videos (even the ones we’ve been allowed to see) that have come out aren’t enough to shock America’s sensibilities, then we’re beyond hope, anyway. When the realization actually does hit, it’ll be too late. It’ll be like the “good German citizens” reacting when the camps were liberated at the end of WWII.

Why, we had no idea. No idea, at all.