There was a recent exchange between Noam Chomsky and Sam Harris here
The issues aren't clear from the exchange. This may clarify:
Chomsky knows Harris's views, Harris doesn't know Chomsky's. Chomsky's been arguing against such views as Harris's and has developed a critique of such views for fifty years. Harris doesn't even know Chomsky's arguments or position. He could know Chomsky's positions and still disagree, but he needs to understand what a radical critique of the US role in the world says and the evidence for it.
Harris is taking a useful aspect of judging moral culpability - the intention of the perpetrator - and applying it to large social events. Chomsky - probably - is fine with the distinction between voluntary and involuntary manslaughter - where the intention of the person is taken into account - but that doesn't mean he thinks you can take powerful, large, social actors and apply the same individualistic criterion for assessing their moral actions.
I think Harris should not focus on intention when determining the morality of social actors' actions. Then he is vulnerable to Chomsky's argument that Hitler claimed good intentions. Harris, I think, should focus on his claim that the US is a more morally developed society and that the actions they are taking, not only are designed to make others morally more developed, but, more importantly, that the results of their actions create moral improvement for others. Harris's point should not be that Clinton or Bush didn't intend to hurt people, but that the effect of their actions over time is moral, social, or economic, improvement for others. If that's the case, then Harris can say the Japanese, the Nazis and Al Qaeda aren't doing that. They may say they are protecting the German people or making the world better by restoring Islam, but they are not. I don't think Harris would be right if he argued that, I agree with Chomsky's view, but I think that's what's crucial in Harris's view.
Harris lists the horrors of American actions over its history, but he doesn't take the next step. The next step is to ask: What social understanding explains all the results of US actions? Harris is saying: Yes the US has done bad, but we're basically creating good. Chomsky is saying: When you look at the results of US actions over time, Harris's explanation doesn't hold up. If the results of a system's foreign policy are consistently bad we start to say that attributing the bad results to unintentional mistakes - the US as well-intended but clumsy giant - doesn't work anymore. That could be a debate between them. But Harris would surely lose. Chomsky has a staggering wealth of knowledge about just those facts and Harris doesn't. But someone else politically knowledgeable might be able to challenge Chomsky's understanding.
What they should be arguing is: what have been the results of US actions in the world over an historical period and what does that tell us about how the social structure of the US functions to produce those outcomes? We shouldn't focus on intentions when we analyze social events, we should look primarily at the results of social actors' acting over time and find an explanation that explains the most data. I've found Chomsky's fact-based, moral and logical view the best.