“Everyone agrees that ~A is ~A” is not a tautology, any more than “Everyone agrees that second-order logic is sound.” is a tautology.
“Unjustified killing” (Murder) is already the intersection of acts which are killing and acts which are not justified. The problem is that different people have different sets of “Acts which are justified” and “Acts which are morally wrong”.
“Everyone agrees that ~A is ~A” is not a tautology, any more than “Everyone agrees that second-order logic is sound.” is a tautology.
“Unjustified killing” (Murder) is already the intersection of acts which are killing and acts which are not justified. The problem is that different people have different sets of “Acts which are justified” and “Acts which are morally wrong”.
I don’t think you and JoshuaZ are having a substantive disagreement.