The Mujahedin-e Khalq (MEK) is an Iranian dissident group that has been designated by the State Department as a Foreign Terrorist Organization (FTO) since 1997. It is one of the main groups that seek to foment war against Iran and hopes to be installed as the Iranian government in the event of an invasion that overthrows the current government. It has put on its generous payroll a large number of Washington insiders from both parties (of course) who are lobbying on its behalf.
Glenn Greenwald provides the text of two op-eds by Jeremiah Goulka about the MEK and how it operates. Goulka worked as a lawyer in the Bush Justice Department and then as an analyst with the RAND Corporation, during which time he got to observe close up the workings of the group, which he labels a cult.
It is worth reading the op-eds about this group that has got friends in high places that are pushing for war with Iran.