AP Explains: Long reach of Iran's Revolutionary Guard

Iran's Revolutionary Guard, designated a "foreign terrorist organization" by the Trump administration on Monday, evolved from a paramilitary, domestic security force with origins in the 1979 Islamic Revolution to a transnational force that has come to the aid of Tehran's allies in the Mideast, from Syria and Lebanon to Iraq.The force answers only to Iran's supreme leader, operates independently of the regular military and has vast economic interests across the country.