Even so, it's hard to write off the killing of a 76-year-old man in a wheelchair or the calm execution of six children huddled in a room as "the fog of war." No, it was a war crime, pure and simple.

But this wasn't ultimately a case of Marines protecting their own and disregarding the lives of slain Iraqis. While some commanders in Iraq were indeed callous about the attack early in the investigation, there was eventually a real investigation and the filing of formal charges against eight of the leaders and perpetrators.

Even though we now have a pretty good idea what happened that day, it's incredibly hard to prove it in court without the active cooperation of reliable witnesses. Alas, as the Associated Press reports, "The prosecution was also hampered by squad mates who acknowledged they had lied to investigators initially and later testified in exchange for having their cases dropped, bringing into question their credibility." And the few Iraqi survivors declined to testify, fearing for their safety.

While Wuterich admits to telling his men to "shoot first and ask questions later," he claims "the intent wasn't that they would shoot civilians, it was that they would not hesitate in the face of the enemy." While that strains credulity, it opens room for reasonable doubt.

Sergeant Sanick Dela Cruz testified that Wuterich shot people at close range and told him, "if anyone asks, the Iraqis were running away from the car and the Iraqi army shot them." But, again, the fact that Cruz himself admitted to taking part in the killings -- and urinated on the skull of one of the dead Iraqis -- but was given immunity in exchange for his testimony could surely have diminished his credibility.

In the end, then, prosecutors apparently reckoned that a plea bargain to a relatively minor crime, but one that would end Wuterich's Marine career in disgrace, was the best they could do.

Awis Fahmi Hussein, who survived the attacks, lamented, "I was expecting that the American judiciary would sentence this person to life in prison and that he would appear and confess in front of the whole world that he committed this crime, so that America could show itself as democratic and fair."

Unsatisfying as it seems, a democratic outcome is exactly what we got. In an authoritarian society -- probably even in today's post-Saddam Iraq -- governments will happily sentence citizens to jail to slake the public thirst for justice. In a liberal democracy, however, we put a very high burden on the state in taking away the liberty of a citizen accused of a crime.

Wuterich and several of his squad mates are almost certainly guilty of war crimes. That he got such a light sentence and the others got off Scot free will doubtless rub salt in the wounds of families who sought justice, And this outcome may well harm America's image in a part of the world where it is already poor. But, ultimately, preserving the fairness and impartiality of the American legal system is more important, and we should be glad that it won out. That's a painful and difficult compromise to make, but the fact that it's difficult and it happened anyway is exactly why we should be glad we live in a liberal democracy. If we were to lower the bar to make it easier to convict those we "know" are guilty, we would also make it easier to unjustly imprison the innocent.

From O.J. Simpson to Casey Anthony to the hundreds of cases that don't garner national attention, the America court system routinely exonerates people that "everyone knows" are guilty of murder. Even more frequently, people accused of major crimes are allowed to plea down to lesser ones when prosecutors fear they won't be able to convict or otherwise don't want to risk going to trial.

That's not satisfying. It's probably not even justice. But it beats the alternative.

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