Should have ignored US opposition and done it back in 05, 06. Now they may have to wait till a crisis level is reached. Which also makes nuclear preemption more likely.
Then, nuclear pre-emption by ballistic missiles will be necessary because the US Navy will shoot down Israeli planes and Iran will have that Russian anti-air system up and running. I agree that Israel needs to do it NOW. Waiting for the next Democrat President who will have a fully consolidated Total State in America will be suicidal.