As there are cases in which war can be morally justified, Catholics are free to disagree over whether any particular war is justifiable. There is never any case in which abortion, euthanasia, embryonic stem-cell research, or human cloning is morally justifiable because they all involve the illegitimate killing of an innocent human being. No Catholic can ever support them. Thus, a pro-life Catholic who properly rejects the immoral killing of an innocent human being can at the same time believe that a particular war is justifiable based on Catholic just war doctrine.
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