Here is the flaw to your argument.
Hamas didn't just wake up and start a war on 7 October. They did it as retaliation for various acts by Israel. They did it due to a false sense that they were defending their country and their people. They felt it was necessary and proportionate. They were provoked by x, y and z.
Israel did not wake up and decide to flatten hospitals. They did it as retaliation for various acts by Hamas They did it due to a false sense that they were defending their country and their people. They felt it was necessary and proportionate. They were provoked by x, y and z.
Assigning sole blame assumes single events are not connected. They are.