Why are there more Palestinian deaths than Israelis?

Someone I care deeply about just posed a question that might seem obvious to some, but requires response, over and over and over. Why are there more Palestinian deaths than Israelis? The "simple" answer is: Hamas used more than 800,000 tons of cement and steel to build terror tunnels into Israel instead of building shelters and hospitals and schools and housing for Palestinians. Hamas has tried to kill thousands of Israeli civilians, but Israel has dedicated itself to protecting its own population (Iron Dome, every building having, by building code, a bomb shelter). The disproportionate number of deaths in Gaza is based on its leadership valuing terror over life. I hate that this is true.