The argument is that the IDF is targeting enemy combatants, and not deliberately targeting civilians (unlike, e.g. Hamas). The existence of non-combatant casualties alone does not imply terrorism.
This is not as simple as it looks. Hamas does indeed target civilians, but what really put the wind up Israel on October 7 was that they successfully overran 2 military bases and mounted a serious attack on a third, although that was repelled. Per Israeli media, the government there had significant prior warning (months or maybe as much as a year) but dismissed the intelligence in the belief that Hamas lacked the military capability and was just LARPing.