Śrīmad-Bhāgavatam 1.7.36
Blended reading (Sanskrit + English inline)
An enemy who does not resist is never killed by a warrior who knows the principles of religion. Formerly battles were fought on the principles of religion and not for the sake of sense gratification. If the enemy happened to be intoxicated, asleep, etc., as above mentioned, he was never to be killed. These are some of the codes of religious war. Formerly war was never declared by the whims of selfish political leaders; it was carried out on religious principles free from all vices. Violence carried out on religious principles is far superior to so-called nonviolence.
Mattam means intoxicated because of liquor etc. Pramattam means inattentive. Unmattam means crazy because of planetary influences or disturbance of vāta in the body.
My note
Source: vedabase.io