Iran

The country which will not be invaded by the USA since, unlike Iraq, Iran has a missile range which can reach Europe, and a modern radar and communications system not to mention approximately an army, including both conventional and revolutionary personnel, of about 750,000 strong. Furthermore attacking Iran, the third largest oil producing country in the world, would dramatically increase oil prices. Notice that Iraq, despite having such a low production of oil, was able to increase the price of oil dramatically. The government also contributes to the stability of Afghanistan, Iraq, and virtually the entire eastern portion of the Near East. So any attack would compromise everything hat the USA tried to do in Afghanistan and Iraq. Furthermore, it has been historically shown that any empire that tries to conquer the modern day Iran either losses control of it in about a hundred years, gets destroyed by Iranians, or eventually is taken over by Iranian administrators since the guys who have conquered Iran do not have a clue about running the governments. And given the current case of Iraq, the USA certainly falls under that category. Furthermore, if the USA attacks Iran, a country with three times the land and populous of Iraq, would very dangerously stretch US forces too thin to effectively engage in an actual threat from another country.