England served jail time and was dishonorably discharged. The others in Abu Ghraib were also punished in accordance with General Court Martial proceedings, so I'm not seeing the "ZERO punishment" part of that.
Well, the OIC for Abu Ghraib didn't get court-martialed or relieved for dereliction of duty; did they? It was a case where a systematized culture of impunity for bad acts was condoned until it became a public relations issue; at which time only those at the lowest level were publicly punished; and the responsibility for allowing such a culture to flourish was never properly accounted for.
As with much of American society these days, the application of justice is capricious and unpredictable; with the signal exception being that the upper echelons suffer fewer consequences than the grunts who do the work.
There's a good This American Life episode interviewing England. She doesn't exactly portray herself in the most flattering light (which is why I think she's telling the truth) and it's interesting to hear what she has to say about the before, during, and after.