FILE - In this Feb. 13, 1979 file photo, a large picture of Ayatollah Khomeini hangs from tank gun barrel in front of Niavaran Palace in Tehran, Iran. Monday, Feb. 11, 2019 marks the 40th anniversary of the Islamic Revolution in Iran, which overthrew the caretaker government left behind by the cancer-stricken Shah Mohammad Reza Pahlavi, who had left the country only weeks earlier. (AP Photo/Aristotle Saris, File)