Marquez-Almanzar v. INS, __ F.3d __ (2d Cir. Aug. 8, 2005) (voluntarily enlisting in the United States Army, serving for eight years, swearing allegiance to the U.S. Constitution, registering for the Selective Service, and completely immersing ones self in American society is not sufficient to qualify as a "national" of the United States for immigration purposes).
http://caselaw.lp.findlaw.com/data2/circs/2nd/034395p.pdf