This was a direct response to claims that the U.S. blocked Iranian journalists from coming to the U.S.  Koppel, whose groundbreaking coverage of the Iran hostage crisis morphed into ABC's "Nightline" in 1980, traveled throughout Iran for three weeks for the two-hour special.
Koppel, whose pioneering work on the Iran hostage crisis led to his role as host of "Nightline" at ABC in 1980, undertook a two-hour special about Iran after traveling throughout the country for three weeks. This was in response to claims that the U.S. had blocked Iranian journalists from entering.