Modern ethics of war debate comes mainly from the Catholic Just War tradition
A war justified by religion is a holy war:
o A holy war is always said to be a good war.
Beginning in the 1500s (พ.ศ.1950+),some Catholic priests and others began argued that religious differences were not a just reason for war.
The idea was to take religion out of ethical reasons for war.
o The rules controlling war would be secular and legal.