Jay Tea of Wizbang has a two-part critique of the Geneva Conventions see here and here. I think he’s painting too rosey a picture of the Geneva Conventions. A primary purpose for becoming a signatory of the Conventions is to secure good treatment for your soldiers when they are taken prisoner by the enemy. Since we became signatories we have never faced an enemy that adhered to the provisions of the Conventions whether they were signatories or not. We have occasionally and incidentally violated the Conventions. Our opponents have violated them systematically.
Additionally, there are cases in which the Geneva Conventions achieve precisely the opposite of their intended result. As I mentioned earlier today the ban on chemical and bacteriological weapons actually enticed the Japanese to secure these weapons under the assumption that their opponents would not respond in kind. We face a similar problem in Iraq. The thugs we face are using the Conventions as a roadmap for identifying strategies to use against our forces.