Washington, Dec. 19--(AP) Former President Bush suggested Wednesday an American captured while fighting with the Taliban in Afghanistan committed treason and recommended how he should be punished. "I thought of a unique penalty: Make him leave his hair the way it is and his face as dirty as it is and let him go wandering around this country and see what kind of sympathy he would get," Bush said on ABC's "Good Morning America."

Bush said his son, President Bush, was not displaying sympathy when he referred to the American, John Walker, as "this poor fellow." The president's mother, Barbara Bush, added: "I think the president meant that he's obviously demented. ... He did something terrible." "He meant just sad," said the former president.

Mrs. Bush: "It is sad when someone is so sick that he would cooperate with ..."

Bush: "The enemy."

Mrs. Bush: "That's right. The enemy."

Bush: "He's done. There's no arguing that. There's nobody can get away from the fact that's what he was doing. Unless somebody thought he was held captive against his own will. I guess in fairness we ought to say, 'Well let's wait to see what comes out of it.' But I don't think the president was being sympathetic at all when he used that expression."

Interviewer Diane Sawyer asked: "So it has to be treason?"

Bush: "Well, I don't know. Treason is defined as aid and comfort to the enemy. Well, if you're fighting with the enemy, I guess you're giving them aid. This guy doesn't look like he could be too staunch a fighter but nevertheless, he's on the wrong side. I don't know technically what you'd call it, but I'm so offended by what he allegedly has done. ... I mean, he's just despicable."

Walker, 20, who is from San Anselmo, Calif., was captured with other Taliban forces in northern Afghanistan last month. He is being held on a U.S. ship in the Arabian Sea. There has been no indication what he will be charged with or how his case will be handled.