Never forget
Americans need never forget this expense could have been restricted to a perhaps necessary and by now concluded war in Afghanistan.
The necessity of the war in Iraq is not borne out by the effects of the invasion. Is there some secret logic to causing the forces that offend each other to interact as this invasion seems to have done? There seems not to be. It is merely an overhang of the colonial era when imperial authority controlled peoples who were considered inferior. The world may have changed, perhaps the politics of war will follow.