I can't stand the alarmist CNN, where everything (I mean everything) is called "breaking news". Whenever CNN declares something as breaking news, it's worth looking at other sources. CNN loves hyperbole to drive its ratings up.
Iran has "vowed to" reciprocate - not the same thing as having already implemented it. I don't know how many people on this forum are traveling to any of the 7 banned countries (Iran, Iraq, Somalia, Libya, Sudan, Syria, Yemen) and are worried about re-entry, but I'm guessing not too many. I feel for the tech workers who go and visit family and now have to worry about getting back in (hence the Google warning to its employees).
https://www.theguardian.com/us-news/live/2017/jan/28/world-digests-donald-trumps-order-to-ban-refugees-from-muslim-countries