Originally Posted by
iad2jfk
-Any country in which the US is on bad terms with the government, for example, Iran
Let's assume that you want to travel from the US to Iran and back to the US, probably with a connection in Istanbul and Doha.
You still need to take two passports, both Italian and US, but you would be using an Italian passport all the way to Iran, and on the Iranian exit point, while presenting a US passport to the check-in agent on the way back to the US.
Would it create problems in Iran? What if they find out that you have both an Italian and US passports?