The precedent was set when the God of "love" Jehovah selected only the Israelite`s as his chosen people in the Hebrew bible { O.T.} and instructed / participated with his chosen people to commit genocide on many Nations killing all and sundry in the process men women children and the elderly "don`t feel sorry for them "
E.G. 1 Sam.15:3
Their are many more examples in the O.T. of Jehovah God instructing his chosen people out of all nations to commit genocide against non Israelite`s .
And if you believe the Bible ,what ? their were no babies women men young and old as well as children ? that were drowned in the flood ?
And what was the point of killing off all of the land animals and bird population ?
Apparently none of the marine life were extinguished ? in the flood ?