link to proposed U.S. Senate Bill S.3081 - sec. 5 below, indef. detention of U.S. citizens

SEC. 5. DETENTION WITHOUT TRIAL OF UNPRIVILEGED ENEMY BELLIGERENTS.

An individual, including a citizen of the United States, determined to be an unprivileged enemy belligerent under section 3(c)(2) in a manner which satisfies Article 5 of the Geneva Convention Relative to the Treatment of Prisoners of War may be detained without criminal charges and without trial for the duration of hostilities against the United States or its coalition partners in which the individual has engaged, or which the individual has purposely and materially supported, consistent with the law of war and any authorization for the use of military force provided by Congress pertaining to such hostilities.