Artful Dodger: It is important to differentiate between military combatants and criminals. In the case of the former, you are right that the fact that they were caught on the battlefield fighting against "our" forces is sufficient to detain them and keep them at some place until the war ends. However, they must not be interrogated (let alone tortured) and they have to be returned back to their homes after the war is over. This is why the US decided not to grant the people detained in Cuba the POW status. But when they did that, they would automatically have to treat them as criminals and now you really would need more evidence (like video tapes with them committing a terrorist act, documents, confession, etc.). And that's what the US didn't want to do either, for obvious reasons. But, it is illegal not to grant the POW status and to deprive a person from the rights stated in the Declaration at the same time. Some presidential order cannot abrogate Geneva Treaties and the Universal Declaration of Human Rights.