Crimes have been committed: those responsible will be punished.

Let me ask you this: do you think what happened at Abu Ghraib is the logical outcome of a US policy decision to use abuse - and in some cases torture - as a tool in the fight against terrorism? And if this is the case, can we bring those responsible (eg. Donald Rumsfeld, assuming he is responsible) to justice without compromising the war in Iraq?

Apart from that, what has happened here is that a sophisticated weapons system of which we were rightly proud, turned out to have a flaw and has harmed people against whom it was not aimed.

This so-called sophisticated weapons system imprisoned thousands of innocent Iraqis at Abu Ghraib, many for months on end, and inflicted abuse on many. It has done the same - and maybe worse - at other prison complexes in Iraq and Afghanistan (see eg. this). How can you say it was not aimed this way? It seems to me that the flaw of which you write is really bad policy and it won't be corrected until this policy is put under scrutiny.

BTW I accept your general argument that the scandal does not affect the moral case for invading Iraq. I just don't share your faith that all those responsible will be brought to justice.