It was a successful operation designed to find and kill Zarqawi, and is also regarded as responsible for finding and killing many insurgents. It was also riddled with abuse, torture and murder of prisoners:

Its motto: "If you don't make them bleed, they can't prosecute for it." McChrystal appears to be the anti-Petraeus. No wonder Cheney loves him. But why then did Obama pick him for Afghanistan? In the wake of horrifying news of unintended civilian casualties, in a war where the US is already intensely unpopular, Obama has picked a leader who can be directly linked to the worst images and incidents of prisoner torture and abuse under Bush.

And one can't help but wonder at the same time: is McChrystal the reason for the sudden volte-face on the abuse photos? Their resurfacing would make hearings very awkward.