So is Israel supposed to ignore the attack within their borders? They would have been happy enough with Palestinians living beside them if they could remain peaceful but no, they let Hamas rule them and use their space for attacking Israel and when they went into Israel and killed civilians, they crossed one line that should never have been crossed. Ignore it and it will embolden more attacks. Don't ignore it, and deal with the root causes. You must know about root causes. Every leftist throws around that buzzword.