And Germany's situation in WWII was far worse than that of the US. The point is that if Hamas ceases firing it's missiles, Israel's retaliations will cease aswell, as they did during the cease-fire, when Hamas lowered it's rocket barrage numbers (but didnt totally halt them). A defending nation does not have to just 'sit tight' when attacked. Infact, it can, and will, respond disproportionately in order to halt attacks against its citizens.