Under that criteria the Martian would conclude he was a U.S. soldier. If that Black Confederate cook, teamster, musician or nurse was in a Confederate uniform, carried on a roster as a cook, teamster, musician or nurse, fed, sheltered and payed by the Confederate government, occasionally picked up a weapon when the unit was engaged in combat but was not listed on the roster by a rank, would that same Martian -especially if he had pro-Confederate leanings- reach the same conclusion as the former described by you? Of course he would which counters your argument that an assigned rank (private, &c.) on the roster is prima facie that the Black was a Confederate soldier.