Sandy asks that question in connection with a possible violation of the Iraqi Constitution. (Like him, I have no idea whether there was such a violation.) As a general matter, I would think that a constitutional violation counts on the "negative" side of the ledger you're keeping to add up the good things and bad things about the behavior you're being asked to evaluate. It's on the negative side because there's a rule-of-law cost associated with constitutional violations (that are conceded to be such). Other things on the positive side of the ledger might outweigh the rule-of-law cost plus whatever other costs there might be to the behavior. But, I think, it would be mistake to say that the "mere fact" of constitutional violation counts for nothing on the negative side.
So, for a provocative example, perhaps impeaching President Obama would be constitutionally lawless but on balance justified. I think what's interesting about Sandy's question is that U.S. constitutional discourse desperately wants to avoid conclusions in that form, and therefore pushes people to say that the actions they think are politically justified are also (and independently) constitutionally justified or even required.
So, for a provocative example, perhaps impeaching President Obama would be constitutionally lawless but on balance justified. I think what's interesting about Sandy's question is that U.S. constitutional discourse desperately wants to avoid conclusions in that form, and therefore pushes people to say that the actions they think are politically justified are also (and independently) constitutionally justified or even required.