Honestly, there should be no need for warning.
When you sneak attack a civilian population with the kind of barbarism they employed, they should expect retribution of some kind and have moved everyone they value to safety BEFORE they carried out this atrocity.
That they didn’t displays an arrogance that is unfathomable, and is also an indictment of Israel for not responding more decisively in the past. IOW, the muslims should be expecting it and be prepared for it. Thus no *warning* by Israel should be necessary.
I wouldn’t frame it as arrogance; they fully expect Israeli response.
They won’t ever move their civilians in anticipation of a response.The civilians are merely fodder for the public relations campaign. Or hostages to preclude an attack - that’s historical and current record.