It's really quite simple. You've set up a phony dichotomy wherein one either supports the killing of all innocent civilians used as "shields" by Hamas, or one is somehow morally obliged to argue that Israel has no right to exist or defend itself.
It's a bullshit dichotomy.
You're arguing an "either/or" situation when in fact there are many other alternatives.
Nope. Never. Every time people are easily able to figure it out in a matter of seconds.
In the grand scale of things it's probably one of the least important things I can think of.