A
war policy where no distinction is made between enemy
soldiers in action and
non-combatants. Black flag policies have the tendency to lead to
massacres and other such things that bother modern people; hence, fighting a war this way is against
international law now. The best example of a black flag policy can be found in the
Old Testament book of
Joshua; after he took the city of
Jericho, every man, woman and child in the city was killed.
Interestingly, Stonewall Jackson originally wanted to fight in the American Civil War under a black flag policy; he viewed the war as a holy struggle, with the South (obviously) on God's side. (Actually, his view of the war as having a religious nature was far from uncommon, on either side.) Fortunately, cooler heads prevailed on him to obey the usual courtesies regarding keeping prisoners safe and avoiding intentional harm to civilians.