I would if he were a citizen.
But . . .
Section 349 of the Immigration and Nationality Act (8 U.S.C. 1481) states that U.S. citizens are subject to loss of citizenship if they perform certain specified acts:
1. obtaining naturalization in a foreign state (Sec. 349 (a) (1) INA);
2. taking an oath, affirmation or other formal declaration to a foreign state or its political subdivisions (Sec. 349 (a) (2) INA);
3. entering or serving in the armed forces of a foreign state engaged in hostilities against the U.S. or serving as a commissioned or non-commissioned officer in the armed forces of a foreign state (Sec. 349 (a) (3) INA);
4. accepting employment with a foreign government if (a) one has the nationality of that foreign state or (b) an oath or declaration of allegiance is required in accepting the position (Sec. 349 (a) (4) INA);
5. formally renouncing U.S. citizenship before a U.S. diplomatic or consular officer outside the United States (sec. 349 (a) (5) INA);
6. formally renouncing U.S. citizenship within the U.S. (but only under strict, narrow statutory conditions) (Sec. 349 (a) (6) INA);
7. conviction for an act of treason (Sec. 349 (a) (7) INA).
I see at least four possible legal reasons to conclude that he had lost his citizenship and is due no rights under law.