In the U.S.-Mexican War of 1846-1848, some recent Irish immigrants to the U.S. defected to the Mexican side, forming the San Patricio Brigade. There is a monument to these guys in Mexico City today.
The U.S. government, on capturing them, hanged the ones who had defected after war was declared and branded the ones who had defected before war was declared.
My own preference would have been to not punish them, and let them live their lives in Mexico. They were defending fellow Catholics against an imperialist war of aggression, and incidentally probably trading the ill-treatment and discrtimination they experienced in the U.S. Army for the higher status and gratitude they got in Mexico.
Second example: the American defectors in Laos, killed by U.S. deployment of nerve gas according to the controversial CNN documentary “Blowback.” They didn’t get any trial or tribunal, they were simply killed and their existence covered up.
In this case, I would prefer not to have punished them either, since the U.S. shouldn’t have been there in the first place.
Third example: at least two Americans died fighting for the guerrillas in El Salvador. It was revealed during the Iran-Contra hearings that U.S. forces were secretly active in combat there, although it is doubtful that these two ever encountered them.
Not only would I not want to punish those two American guerrillas, I would have celebrated them as heroes. They were fighting against a government controlled by death squads and oligarchs. The U.S. was definitely on the wrong side in that one.
John Walker is the defector whose actions I approve of the least, and his cause is definitely less sympathetic than the others. But just because I like his cause less, I don’t advocate anything harsher for him than what I would want for the others. He should be allowed to stay in Afghanistan, or if the Afghans don’t want him, some fundamentalist country more to his liking.
Since he joined up before war was declared, maybe he could benefit from the “San Patricio” precedent.
By the way, I’m also against the death penalty in general, and opposed to military tribunals and Bush/Ashcroft’s constitutional power grabs. So maybe my opinion doesn’t count anyway.