I know there are a number of folks who are interested in General Lansdale and my studies have given a bit broader background than is sometimes discussed so I thought I would share it.
Generally everyone knows that Lansdale was Air Force, detached to support the CIA in the area of special operations and related political action, primarily in the Far East.
But many may not know that Lansdale was actually head of the Saigon Military Mission in the mid-1950’s. He arrived in 1954 and initiated psych war and political action efforts in the south and also paramilitary operations against the North. His propaganda is credited with producing much of the fear that led the huge Catholic exodus from the North. Later he became head of the joint U.S./French Training Relations and Instruction team working under the National Security Division – in reality his real work was building the U.S. backed Diem regime. Lansdale helped launch the first major military campaign against the Vietminh in the South and by 1957 tens of thousands of their cadre had reportedly been killed (anyone who was anti government seems to have been open to classification as Vietminh). Lansdale ended his tour in Vietnam in 1959 and rotated back to Washington, being assigned to the Joint Chiefs staff under General Erskine in the Office of Special Operations.
After JFK’s election, Kennedy had called for an in depth review of the Vietnam situation and was particularly interested in the lack of any success in the covert operations the CIA was conducting against North Vietnam.
Lansdale had returned to Vietnam to study that subject among others and produced a report which favorably impressed JFK and ultimately (following the Bay of Pigs disaster) led to JFK calling on Lansdale to lead the Mongoose project against Cuba. It was good timing for Lansdale since the OSO was disbanded at that point and all of its officers assigned to other duties. Actually under General Erskine, the OSO had carried out a variety of intelligence roles ranging from special operations coordination to participation in reconnaissance satellite development. The new Defense Secretary (McNamara) apparently had nothing against Erskine but thought that many of the OSO work was duplicate in nature and that its staff would best be distributed.
In general the Joint Chiefs and the Army in particular were not nearly as excited about the potential for special operations as JFK, however in a 1962 response to the Presidential interested it created the Office of Special Assistant for Counter Insurgency and Special Activities. SACSA served as something of a successor to OSO, although with a much more focused mission. It would have several chiefs during the 1960’s and early 70’s, fading away circa 1974 as the last chief was reassigned. SACSA did play a role in Vietnam with MACV/SOG, the pacification program and with what became known as Phoenix.
As to Lansdale, while Mongoose had not succeeded it had not really failed either – it had been superseded by the Cuban Missile Crisis and agreements with the Russians. JFK reportedly remained a real fan of Lansdale and his high profile, aggressive special operations attitude and actually floated him as Ambassador to South Vietnam.
There was strong push back on that both from the State Department (which feared personal influence with Diem) and from the Joint Chiefs (who much preferred conventional warfare over special operations). Kennedy then proposed him as Chief of the newly created Military Assistance Advisory Group to Vietnam but eventually settled by putting Lansdale in a staff position as assistant to the Secretary of Defense. That would have been a pretty difficult position given that McNamara seems to have had limited regard for Lansdale and his own set of issues with the Joint Chiefs.
During a fact finding trip to Vietnam with JCS Chief Taylor, Lansdale apparently ignored his instructions not to resume his high level political contacts, following the trip Lansdale was assigned to anti-Cuban counter insurgency- but any real functions he might have had as Assistant Secretary of Defense for Special Operations were functionally taken over by the new SACSA group. In the summer of 1963, while on a fact finding tour of Latin America he received notification from the Pentagon that he was being retired from active duty. He had become odd man out.
Reference for the above include Robert Gillespie’s book Black Ops Vietnam and John Prodos books President’s Wars and his biography of William Colby.