IMHO the problem has become one of a lack of leadership and follow-up; the US had goodwill from just about every country - even Iran, Cuba and Venezuela - in the days following 11 September 2001 - but the administration managed to successfully p!ss that all away.
The Hicks thing is part of that. Right or wrong, the processes put in place were flawed. 'Fog of war' and all that aside, the process then became one away from the battlefield and it has been very poorly handled.
The one thing Blair has done right is to see that the whole Gitmo process was going nowhere, was going to end up becoming a cluster-fcuk and defused it in the UK before it became a political issue. Now, far from being forgotten, the administration has let this become a political black hole.