Can Israel go against Iran without the support of the US?
If someone was to attack your home using a gun, and you see your own gun on the table, would you pick it up right away to shoot back, protecting your own home? Or would you wait till you got your neighbor's permission? Of course not. So why should Israel not be able to also protect herself if attacked? Israel is a Nation, and a Nation has a right to protect itself.
Israel is always being attacked on a daily basis from within. For the most part, no cover by the media. I might be wrong, but I think they are the only democracy in that area. I'd rather be there than in any other state in the Middle East.