Francisco Rey Marcos, a researcher with the Institute for the Study of Conflict and Humanitarian Action (IECAH), writes (emphasis mine):

" Violence in any armed conflict may seem 'indiscriminate', merely the product of chaos, but in fact it is rarely so. On the contrary, there is always a rationale of some sort. ... In Iraq, more than in the earlier wars in Kosovo and Afghanistan, it may be that humanitarian agencies -- their independence already stretched -- are being widely perceived as part of the framework created by the intervening forces, as actors in the armed conflict, and not as impartial providers of aid and protection.

And make no mistake, this has not come about by accident.

When British Prime Minister Tony Blair said during the Afghan conflict that 'this war has three dimensions: the military, the political and the humanitarian one', he reinforced the impression of a hidden agenda behind humanitarian action.

In the case of Iraq, coalition governments have also been financing the most sympathetic, least publicly sceptical NGOs while ignoring others less pliable, so it is easy to see how this perception of ordinary Iraqis took hold. "

I've had cause to make this point before: No one in a conflict situation is perceived as neutral by the participants.