When it comes to Department of Defense doctrine on military treatment of detained persons, “unlawful enemy combatants” are a thing of the past. That term has been retired and replaced by “unprivileged enemy belligerents” in a new revision of Joint Publication 3-13 on Detainee Operations, dated November 13, 2014.
Among other changes, the revised Publication adopts Article 75 of the First Additional Protocol to the Geneva Conventions which provide minimum standards for humane treatment of detained persons. It also presents expanded discussion of biometric capabilities that are applicable to detainees.
The previous edition of Joint Publication 3-13, published in 2008, is available here for comparison.