My main concern with the Mideast situation is purely economics. The minute Israel has proof Iran is helping out then Iran will be going bye-bye, along with their oil. I'd place my money on oil reaching $90/barrel from that but I don't think the $100/barrel will be reached. However, the resulting shockwaves cause by hyper-expensive oil will not be pretty.
I don't think there will be any organized terrorist attacks inside the USA though. Most of the terrorist's money and leaders will be busy trying to saved their own asses from the big boot that is currently kicking them (Israel). There may be some "lone wolf" type attacks here in the USA, but nothing on the scale of 9/11 or 7/11 (UK), Madrid train bombing, India's recent train explosions, the Beslan school massacre, or any other "prostylizing" by the religion that can not be named.
-Blast