spartans_in_darkness

EO
1. 4. (c)
Tep SEe~ETiJ'eeMIlHi;X1
NSA. Without the individual texts (there were
two of them), it is difficult to determine whv there
are critical differences in the translations and
more importantly, to understand why two separate
North Vietnamese messages were combined
into one translation by NSA.
(U) Before a discussion can begin, it is necessary
to understand how the Gulf of Tonkin incidents
came to happen as they did, and what their
significance was for the Johnson administration.
To do that, we need to consider the Desoto mission
that the Maddox was conducting at the time,
as well as the Defense Department's OPLfu'\-34A
missions against the Democratic Republic of
Vietnam (DRV).Itwas the convergence of the two
that embroiled that ship in the crisis in the
Tonkin Gulf.
(U) The Desoto Missions
(3//30 Desoto was the covername for a U.S.
Navy signals intelligence collection program
begun in 1962 in which naval SIGINT direct support
units (DSU) were placed on board American
destroyer patrols alon the Asiatic coastline in the
western Pacific
some assertions, the Desoto missions were not
the functional or operational equivalent of the
ubiquitous Soviet elecfronic collection trawlers."
The Desoto missions primarily served the mission
needs of local commanders, although they
received technical support in the way of technical
working aids and intercept data from NSA.
(S//SI)
(U) The Desoto patrols had a two-part mission:
to collect intelligence in support of the
embarked commander and higher level authorities
and to assert freedom of navigation in international
waters. The earlv Desoto missions in the
Waters
ad been tracked by the coastal radar surveillance
networks belonging to the naval forces
I
IWhile an occasional communist
patrol ship would come out and shadow the
U.S. patrol, little else happened.
(U) However, when the Desoto patrol first
was proposed for the waters in Southeast Asia, its
c:,//go Physically, Desoto mission destroyers
were unique in their configuration - a small van
lashed to the ship's deck which housed intercept
positions for voice and manual morse communications.
There also was a position which intercepted
noncommunications emissions such as
radars, referred to as electronic intelligence or
ELINT. Finally, a communications position,
which allowed the detachment to send and
receive messages from the other monitoring stations
in the area, as well as other SIGINT organizations
and commands, via the Criticomm communications
system was located in the hut. The
hut was manned in shifts from a complement of
twelve to eighteen officers and men from the
Navy's cryptologic element, known as the Naval
Security Group (NSG). However, contrary to
(U) Desoto mission van
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