Read about bombing of Berlin by Allies, or bombing of North Korea, by the way. It's how wars are fought, unfortunately. This war is no different. Except... I don't remember anything about supplying metric tons of humanitarian aid for Nazi Germany in WW2? So stop being a hypocrite.
If Western nations are to be sorrowful for Nazi crimes in the 1940a surely the ethnic cleansing of the Arabs is on the table for discussion here…
And it's not just Hamas, it's general hatred against Jews which is nurtured in Palestinian people. In their schools, in their books, they teach their children to hate Jews, to kill them. There just isn't anything like that in Israel — Israelis don't want to kill Palestinians, they'd like to peacefully coexist with them, but again and again they are left with no choice.
Israel left Gaza once, by the way, but that only made Hamas stronger. Appeasement doesn't work seemingly with those who don't truly want peace.