Should it ever come to that Israel would have to strike Iran's launch facilities and Iron Beam will be rushed into service sooner than anticipated.
Israel couldn’t strike Iranian launch sites. How will they do this? You do know the distance between Iran and Israel, I take it. Iran’s sites are buried underground and in mountains. Israel have no ground based missile capability that could reach Iran, never mind take out their launch sites. Israeli planes can’t reach Iran without refuelling, airspace closed off to them. How are they going to achieve this objective? They can’t. You lack any insight into the strategies and messages being sent by these actions. Israel is in a bind now and anyone with any understanding knows this.
To not respond to Iran after promises of retribution will show them as weak. Any response will meet with a further escalation from Iran who have demonstrated that they can strike any Israeli target. Iran have kept it restrained but demonstrative enough to show this. Israel cannot defend against advanced Iranian missiles.