spartans_in_darkness

----- --
Tefl SEeRETlleeMltHNX1
traffic. On 8 June, NSA reported that the level of
North Vietnamese tactical radio communications
had increased almost fourfold during the early
part of June from the previous period in May,
probably in reaction to attacks along its coast. It
also reported that DRVnaval patrols now seemed
to cover its entire coastline.P" Clearly, Hanoi was
determined to defend itself resolutely. Whether
or not the Vietnamese believed that the
Americans were preparing for a larger war was
not important. What was critical was that the situation
along North Vietnam's territorial waters
had reached a near boi1. 35
(TSl/SI) The SIGINT support to OPLAN 34A
started at almost the same time as the operations
began. Codenamed Kit Kat, the effort required
that the then current ceiling of 660 cryptologic
personnel in South Vietnam had to be raised. In
February 1964, an increase of 130 personnel for
Kit Kat was approved by CINCPAC. 3 6 The ASA
moved personnel from the Philippines to Phu Bai,
and the Naval Security Group added coverage of
North Vietnamese naval communications to its
site at San Miguel in the Philippines. The Air
Force Security Service units at Monkey Mountain
near Danang increased their coverage of the communications
of DRV navy and coastal surveillance
posts. A small special SIGINT unit at Tan
Son Nhut Airbase, known as the Special Support
Group (SSG), was formed in late February to
coordinate Kit Kat support between the intercept
sites and the Studies and Observations Group.
(8//81) Besides the NSG detachment aboard
the Maddox (USN-467N), other SIGINT elements
that were involved in the events of the next
three days included a Marine SIGINT detachment
(USN-414T), collocated with the Army
Security Agency intercept site at Phu Bai (USM­
626J), and the NSG site at San Miguel,
Philippines (USN-27), which also had a Marine
SIGINT contingent, but the latter was not designated
separately as was the Marine group at Phu
Bai.It would be the intercept and reporting by the
Marine unit at Phu Bai and the navy site in the
Philippines which would prove critical to the
events in the Gulf of Tonkin.
(~//SI) A few last notes before we review the
attacks. It will be necessary to limit the discussion
to the role SIGINT played during the incident.
Other evidential sources, such as that from the
American ships' own radar, sonar, and visual
sightings, will be mentioned in passing simply
because they are part of the story and cannot be
altogether ignored. However, the brunt of the following
discussion will center on the SIGINT evidence
because of its critical role in convincing the
Johnson administration that the attack actually
occurred.
Page 184
Tefl SEeRETifeeMltHIIX1
/
i>:
EO 1.4. (c)