Do any Western thinkers justify killing of civilians in wars?

The Liberal theory of the 'Supreme Emergency Exemption' allows the deliberate targeting of innocent civilians if it is deemed necessary to avoid 'enslavement, destruction of one's political community or genocide (which is not only defined as wiping out people, but also forced relocation of them)'. In other words innocent civilians can be targeted - have any of those arguing this been arrested for promoting terrorism? Nope! To demonstrate how mainstream this opinion is, one needs to simply review the foremost leading Liberal Philosophers of War theory and Political Liberalism (i.e. the Western equivalent of Mulla's and Muftis), John Rawls and Michael Walzer: "Can soldiers and statesmen override the rights of innocent people for the sake of their own political community? I am inclined to answer this question affirmatively...individuals can­ not kill other individuals to save themselves, but to save a nation we can violate the rights of a determinate but smaller number of people...We might better say that it is possible to live in a world where [innocent] individuals are sometimes murdered, but a world where entire peoples are enslaved or massacred is literally unbearable. For the survival and freedom of political communities-whose members share a way of life, developed by their ancestors, to be passed on to their children- are the highest values of international society" (Michael Walzer, 'Just and Unjust Wars: A moral Argument with historical illustrations') "No government can put the life of the community and all its members at risk, so long as there are actions available to it, even immoral actions, that would avoid or reduce the risk....That is what political leaders are for; that is their first task" (Michael Walzer,'Just and Unjust Wars: A moral Argument with historical illustrations') "This exemption allows us to set aside-in certain special circumstances-the strict status of civilians that normally prevents their being directly attacked in war...The [Catholic] doctrine of double-effect forbids civilian casualties except insofar as they are the unintended and indirect result of a legitimate attack on a military target. Resting on the divine command that the innocent must never be killed, this doctrine says that one must never act with the intention of attacking the enemy state by the means of taking the innocent lives of its civilians. Political liberalism allows the supreme emergency exemption...The statesman..is a central figure in considering the conduct of war and must be prepared to wage a just war in defense of liberal democratic regimes." John Rawls 'The law of Peoples' The logic used by Osama bin Laden is indistinguishable from the arguments used by secular Liberal philosophers. Osama says the Muslim world is suffering from enslavement and it is in a state of emergency and the palestinians are suffering from ongoing ethnic cleansing and genocide. Osama and other terrorists are products of the 'modern' world and adopted secular logic in their justification of their immoral actions - which they perceive as 'necessary' for their causes. Quite literally, the only difference between Osama and Western warfare philosophy, is Osama happens not to want to create a Liberal regime. Considering that Nelson Mandela is celebrated as a freedom fighter - despite the fact that Mandela's group bombed shopping malls, cafes and restaurants killing men, women and children (and even fought other groups on the same side) - the only sin is the Ideology you fight for, not the tactics you use.