this is michael walzer. he is a professor emeritus at princeton university and the author of any number of books. there is one i will recommend to you. it is called "just and unjust wars," published in 1977. i read it as a college freshman. it has been through five editions since then. and it is the single most lucid and intelligent study of the ethical aspects of war that i can recommend to you. walzer talks in his book about the principle of double effect. this is a concept that really goes back before him, back to the scholastics of the middle ages. but he offers a good modern formulation that is relevant to what i am talking about today. writes, is a, he way of reconciling the absolute prohibition of attacking noncombatants with the legitimate conduct of military activity. which may unavoidably exposed noncombatants to harm. condition is that the intention of the actor is good. that is to say, that the actor, the person responsible for attack, specific is naming airily at the acceptable affect -- the dea