As a Zionist who's highly critical of Israeli policies & practices in the West Bank & Gaza I don't think alluding to the complex origins of this conflict is whataboutism. Rather it goes deep.
Yet here the imperative couldn't be simpler: Hamas must be destroyed.
Children beheaded...?
I don't know. But they were killed. We know that. And we know Hamas engages in an existential war with Israel & the Jewish People. Read their charter. They're not just (or perhaps even) fighting for land, or recognition, or autonomy. I believe Israel has fought only one true existential war, in '48. Their opponents had more limited goals in the others. But if they don't destroy Hamas, & its psychopathic kid brother, Islamic Jihad, they might find themselves in another. Hamas is the most unreservedly anti-Semitic outlet since Grand Mufti al-Husayni feted Hitler & Himmler.
Delenda est Hamas!