Panetta believes there is strong likelihood that Israel will strike Iran in April, May or June — before Iran enters what Israelis described as a “zone of immunity” to commence building a nuclear bomb. Very soon, the Israelis fear, the Iranians will have enough enriched uranium in deep underground facilities to make a weapon — and only the U.S. could then stop them militarily…

Israeli Defense Minister Ehud Barak may have signaled the prospect of an Israeli attack soon when he asked last month to postpone a planned U.S.-Israel military exercise that would culminate in a live-fire phase in May. Barak apologized that Israel couldn’t devote the resources to the annual exercise this spring…

Israelis are said to believe that a military strike could be limited and contained. They would bomb the uranium-enrichment facility at Natanz and other targets; an attack on the buried enrichment facility at Qom would be harder from the air. Iranians would retaliate, but Israelis doubt the action would be an overwhelming barrage, with rockets from Hezbollah forces in Lebanon. One Israeli estimate is that the Jewish state might have to absorb 500 casualties.