There are a few missing from the list, like the Special Operations Command Intelligence Support Activity (ISA)--which may have another name by now. Officially, it doesn't exist, but its job is to gather intelligence in support of SOCOM operations, including the very black ones. It was formed after the abortive Iranian hostage rescue mission, because the military realized it could not count on the CIA for operational intelligence support. A popularized history of the unit can be found in The Killer Elite by Michael Smith (St. Martins Press), 2007.