If Israel attacked Iran's nuclear facilities, the strike would probably take the form of a complex air assault involving scores of planes that would have to penetrate Iranian air defenses and attack up to a couple of dozen targets simultaneously, analysts say.

"This would be way more sophisticated than anything that's ever been done before," said Charles Wald, a retired Air Force general who led the coalition air campaign in Afghanistan that helped topple the Taliban.

By contrast, Israel's strike on Iraq's Osiraq nuclear reactor in 1981 and an attack in Syria in 2007 were simpler operations that required Israel to hit a single above-ground target. Neither country had sophisticated air defense capabilities.

There would be nothing "surgical" in a strike on Iranian facilities, Wald said.