How well does Atticus feel he should defend Tom Robinson? Is it usual for (White) lawyers to do Thier best for black clients in Alabama at this time?

Atticus feels he has a moral obligation to defend Tom with every ounce of intelligence and strength he has. Atticus thinks this is a case about humanity as much as it is about justice. Atticus wants to give Tom Robinson a chance against a bigoted society. I don't think there were many, if any, black lawyers at the time so if a black man had a lawyer, he would have to have been white.