Security Intelligence in the Middle East (SIME): Joint Security Intelligence Operations in the Middle East,c. 1939–58

Security Intelligence Middle East (SIME) remains an understudied aspect of British intelligence. In many respects it was a remarkable organization. Its wartime iteration was created in haste, ostensibly as a military body but based upon the Security Service's office in Cairo. It evolved into a truly ‘joint’ unit but culturally was closer to the Security Service (MI5) than either the military or the Secret Intelligence Service (MI6). SIME changed dramatically as a result of the end of the Second World War: it became the sole responsibility of MI5; local cooperation between MI5 and MI6 was scaled-down and became the focal point of a broader inter-intelligence service dispute in London; and new nationalist threats caught SIME off-balance and eventually undermined its raison d'être. SIME's contrasting wartime and peacetime iterations provide a useful example of how intelligence agencies respond to external pressures. It also provides a window into wider jurisdictional and constitutional conflicts at the heart of the relationship between MI5 and MI6, both during and after the war. Finally SIME shows practitioners what can be achieved under the right stimulus and what can be lost when that stimulus fades.