Actually, if you are an American citizen, then you have no problems. You can visit Iran and come back home. If you are a foreigner, after your visit, you may have serious problems at the airport. They may not let you in. They will think that you are a spy or a dangerous person. It is really serious. Many people think that just travelling to a country for vacation has nothing terrible. It is very important to carefully choose your destination according to the politics of your country. In this case, Iran is not a good solution for American or foreigners living in the USA. It is sad but it the truth.