If you are not ready to use a nuke ever, it stops being a deterrent. Game theory.

But this situation is not the kind where a nuke is used as a deterrent. If Israel was saying they’re sorry and asking for ceasefire, while Iranians would be absolutely destroying what remains of it and not listening, then yes.

Or, if Iran had a nuke and Israelis were succeeding in destroying Iran.

But neither are true.