A small but significant portion of US convicted criminals [in particular those on death row] are wrongly convicted (and are/have been proveably innocent) and therefore have been and no doubt will continue to be killed unlawfully...

I don't see how wrongful convictions in the U.S. relate to blatent, premeditated murders in Iraq. I suppose that your case could be that allowing for the possiblity of an innocent person being executed is the same as murdering innocents with full intent, but to me they are two different things.

You could also carry this argument beyond death penalties. Innocent people can receive life imprisonment, which is akin to tortuing them for the rest of their lives. This is unfortunate, but it doesn't put any country that imprisons criminals on the same "level" as Iraq.

Any country with death penalties faces this problem. Its a major reason why death penalties are no longer practised in most "1st world" nations. The US being a notable exception here.

I do understand that you think death penalties are barbaric and there is room for discussion there. I just won't agree that what the U.S. does in it's criminal justice system is the same as what Saddam did.