it's also why Germany started WW1 and what made it easy to put all the blame on them (after WW1, WW2 is a different thing)

and also is related to common war crimes iff in a conflict combatants frequently hide as civilians (as a defense by offense will sooner or later lead to attacking random civilians due to mistaking them for hidden combatants)

so I would take that saying with a bit of salt

Guerrilla warfare strategies undercut old saying like this and are essentially what these hacker groups represent