An alien enemy is an individual who, due to permanent or temporary allegiance to a hostile power, is regarded as an enemy in wartime. Under federal law, an alien enemy is a native, citizen, or subject of a foreign nation, state, or sovereign with which the United States is at war. Such a person is considered an alien enemy as long as the United States remains at war as determined through proclamation by the president or resolution by Congress. 8 C.F.R. § 331.1 (2002). During times of declared war, Congress has permitted the president to order the apprehension, restraint, and deportation of alien enemies. 50 U.S.C.A. § 21 (2003).
The term alien enemy, as it is defined by federal law, does apply easily to individuals who belong to organizations that are not affiliated with a foreign sovereign. Nevertheless, the treatment of such aliens mirrors treatment permitted by federal law for aliens who are citizens of foreign nations. In the wake of the september 11th attacks, Congress passed the Authorization for the Use of Military Force Joint Resolution, Pub. L. No. 107-40, 115 Stat. 224, permitting the president to use force to detain and try non-citizens in the war on terrorism. On November 13, 2001, President george w. bush issued a military order [66 Fed. Reg. 57,831–57,836 (2001)] setting forth the military's policy for the treatment of non-citizens in the war against terrorism. The order applies to individuals who are or were members of the terrorist organization al Qaeda; have engaged in, aided or abetted, or conspired to commit acts of international terrorism; or has harbored such a non-citizen.
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