Today, war, an irreparable wrong, is commited in most cases without the slightest notion of ethics and justice.
In the early days of Islam war or fight were only defensve measures which entailed a number of ethical and moral standards. It was so stipulated by, among others, Abu Bakr as-Siddiq, the first Caliph of Islam after the Prophet:
Do not cut down fruit trees. Do not destroy an inhabited place. Do not slaughter any sheep or or camels except for food. Do not burn bees and do not scatter them. Do not steal from the booty and do not be cowardly.