I have posted a paper that I wrote on the Jewish tradition and warfare here. It is an exploration of whether there is a basis for a "just war theory" in Judaism and of what Judaism has to say about the killing of civilians in war. Obviously, I'm posting it now because of what is happening in Gaza - as my first post on this showed I think it is a horrible and very complicated situation. For those just interested in the civilian issue, sections V and VI are most relevant.
Michael Walzer, a Princeton philosopher who has written a lot about the ethics of warfare, has over the last couple of years begun to explore Jewish values and war. Some of his work on the topic is here.