If Hamas declares: you have two choices--either let us go free, or kill massive number of civilians, you have three choices.

Choice one is to let Hamas go free.

Choice two is to take their alternative.

Choice three is to arrange for a better third choice.

If the Israeli government says, "Well, we're killing thousands of people, but what can we do? It's Hamas' fault! We have to kill them and they make it so the only way we can do so is by killing large numbers of civilians!" we can very reasonably say, "Are you sure you're doing as much as you can to avoid having terms of engagement dictated to you by Hamas?"