Israel probably doesn't have the kinds of conventional weapons that would be needed to destroy Iran's most important nuclear facilities, which are buried deep underground or inside mountains. But the world would instantly turn against the Jewish state if it attacked those sites with nuclear weapons. The U.S. has bunker-busting bombs that might be effective in neutralizing Iran's nuclear infrastructure, but then what? The only way to assure Iran wouldn't reconstitute its program somewhere else where it was even harder to strike, is to invade it, overthrow the government and occupy the country. We tried that in Iraq, and we saw how it turned out.