INTELLIGENCE WARNING OF THE TET OFFENSIVE IN SOUTH VIETNAM (PUBLICATION DATE ES

Created: 4/8/1968

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INTELLIGENCE WARNING OF THE TE OFFENSIVE IN SOUTH VIETNAM

(Interim Report)

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working group has been formed underof R. J. Smith, on which CIA, DIA,and the Joint Staff are representee. Thiscompiled dossiers on the raw intelligenceintelligence summaries and judgments receivedUS headquarters before Tat, with emphasis

on thend on the finished intelligence disseminated to senior officers of the governmentesult.

of the crouo from CIA.the Joint Staff visited Vietnam frcno They were Joined there by observersMACV, and the CIA station in Saigon. toarge quantity ofthe delegation received briefingsinterviews, both in Saigon and themany senior officials, US and Vietnamese. US aide, members of the delegation talkedSunker, General Westmoreland,Ambassador Komer, Et. General Cushman,Rosson, Maj. General Peers, Ma;.and the commanding generals of 1stand 4th Infantry Division. Theysnd II Field Forces and the

f III Marine Amphibious Force, anddvisers and the CIA Regional officers in all four Corps Tactical Zones (CTZs). They were briefedbynd by the CIA station in Saigon, and"contacted the Director of Intelligence, Seventh Air Force, NSA Representative Vietnam,he Army Headquarters .Area Command in Saigon. On the Vietnamese side, they interviewed the comrnanding generalsnd IIf the Joint General Staff and his deputy, and the deputy director of National Police. In the course of thesemembers of the group visited Phu 3ai, Da Nang, Pleiku, Caae Enari, Nha Tranc, Bien Hca, Lone 3inh, and Can Tho.

APPROVED FOR RELEASE

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B. General Findings

the DCI informed the President'sAdvisory Board in February, thereboth in Saigon and in Washington, that

the enemy was engaging in his much-advertised "winter spring campaign" and was preparingeries of coordinated attacks, probablyarger scale than ever before- There was evidence in January that some attacks in the highlands nrjcht bffduring the Tet holiday. .In the latter part ot the month it was evicent that other attacks were imminent, and seme of the targets had been lagrTtiiiec. Hotn in Saigon and in Washington this intelligence was cocmunicated to senior military and political officers. eries of actions were taken in Vietnam which recucefl. the mpact of the enemy offensive.

warning thus provided representsachievement for the US intelligenceVietnam. It has no high-level clandestineof the Communist hierarchy andcommunications are for the most It must therefore rely on classictechniques. This is difficult under The intelligence organizationand civil, US and Vietnamese, isthe volume of material it handles isthe recognition of significant reportssources through the blare of backgroundmajor problem. Moreover, the very the wqf leads to the "crying wolf" sv^rironp.

ave little ccubt that at some level of theapparatus lew-level reports could be found forecasting nanv of thede at Tet; We havele doubt that sir.jlar resorts dfltlld Del^^rting tP attacks on many other cities and on. many other dates.

5. The enemy took great pains to conceal his intentions.' Knowledge of his plans was fully com-partmented and the actual attack order wasto attacking units only in the finaloours. Although US and Vietnamesereceived some reports of individual attack plans, probably no Communist officer below the

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ievel of COSVN. front, or military of the full scope of the offersive! Ger moreland believes the Communists sacrificed tion for security, and this is evident in theattacks by units of MilitaryMR S) on the nightanuary, attacks which served to alert the OS command to the much more extensive attacks on the following night.

Despite enemy security measures, conununiva tioas intelligence was able to srovidc clear warning tnat attacksf 'crobablvarger scale than ever beere in the offine. Considerable numbers ot'flieaixa- And iow-grade enciphered enemy messages were read. These messages appeared in many areas of South Vietnam* They included references toattacks, more widespread and numerous than seen before. Moreover, theyense of" urgency, along with an emphasis on thoroughand secrecy not previously seen in such These messages, taken with such nontextual indicators as'increased message volumes and radio direction finding, served both to validatefrom other sources in the hands of localand to provide warning to senior The indicators, however, were notto predict the exact timing of the attack.

C, Impact of the Enemy Offensive

7. Although warning had thus been provided, the intensity^ coordination, and timing ot the enemy attach were not fully anticipated. Ambassador Bunker and General Westmoreland attest to this. The most important factor was timing, ret* US or GVN officials believed the enemv would attack derma Tet, nor aid fhe Vietnamese public. There was coed reason for this: Tet symbolizes the solidarity of thepeople. It is the most important holiday in Vietnam, an occasion observed by all members of very family whether they are Buddhist, Christian, or Communist. The Communists evidently believed they cculd exploit this solidarity to produce an antigovernment, antiforeign, antiwar uprising. This did not take place. The enemy thereforerice in the antagonisms he generated among the urban population.

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he gained enormously in two ways: The GVN's army and police were generally far below their usual state of readiness* and the precedent of Tet made it possible for large numbers of VC to enter the cities without causing alarm. Generalexpected heavy attacks either just before or just after Tet, and as Tet approached and major attacks had not materialized, the Vietnamese Joint General Staff had authorizedercent leaves. Evidence to upset this general belief did not ccme to hand untilours or so before the, attacks were launched, the most important being the premature initiatives in ttR-5. The latter brought the intelligence already available into sharp focus and provided the missing element of timing. In the short time available, US and ARVN units could be alerted and were, but ARVN performance was reduced in many areas byeaves-

second major unexpected element wasof simultaneous attacks mounted. had given theapabilityvirtually all of the points whichin fact attack and ofumber of areas* He waapecific capability for coordinatedin all areas at cnce% More important,of the targets was not anticipated, and Saigon expected attacks on some they did not exsect the offensive to have tnend control stations and poling headquarters as Finally, the quantity of new,in the hands of Main and (Local Forcewho engaged in the attacks Was higher Theifle andntitankwere particularly effective against ARVNthe Regional and Popular Forces,

these specific problems wasbasic one; most commanders andat all levels, did not visualizeas capableaccomplishing his statedthey appeared in propaganda and in captured Prevailing estimates ofn,and local recruitment, reports of low morale.

was transmitted and duly analyzed, but atmosphere is not readily passedeletype circuit. Although "seniorn Washington received warnings in theanuary, they did not receive the full sense of immediacy and intensity which was present in Saigon. On the other hand, with Saigon alerted,nothing further could be done in Washington that late in the game which could affect the outcome.

this general picture, there weredifferences among, the four corps areas. expected assaults on Khe Sanh and Quang TriT receivedocal CIA operation the enemyplan for Da Nang, but not the date. Generalstated that he expected to be attacked duringenemy activities inTZ hadauthority to cancel the Tat truceTZ.

esult both US and Vietnamese forces were better prepared here than elsewhere. Most Vietnamese units were at nearly full strength. The extent andof the enemy's attacks, considerablyexpectations, as did his tenaciously held lodgement in Hue. In general, however, his assaults were easily thrown back.

II CTZ, allied forces in the coastalwere for the most part attacked or. the night

anuary bynits. They did not have the advantage of forewarning which these attacks provided units farther south, nor were they in the "alert" posture of Allied forcesorps. The Allied forces wereigher than normal state of alert, which was, however, directed against the inevitable cease-fire violations rather than attacks on the cities. In the highlands, singularly unlike any, otherntelligence was availablegegee, prisoners,ing specific plansing.Tev FoYtance. Communist plans for attacking Dak To, Pleiku, and Kontum were known well in advance, and the US 4th Division was able to correlate them with enemy This provided one of the fewfor US forces to take active measures against the enemy; Pleiku was the most successful CSof the offensive. Elsewhere in the highlands intelligence was not as good, but there was enough information to lead two of the three ARVN division commanders in II CTZ to cancel all leaves on their

own initiative. We do not believe, however, that these orders were totally effective in recoveringwho had already departed.

It has been noted above that US redeploy-raenta in III Corpa began before mid-January. These movements were triggered by the concentration of three enemy divisions along the Cambodian border north and northwest of Saigon and by indications that these unita were beginning to deploy southward toward the city. In addition, US and ARVN intelligence officers had earlier deducedeorganization of the enemv command structure in MRhich surrounds the Saigon" area, that its purpose was to improve command and control for the coordination of an attack on that city. Ill Corps and II Field Force were puteneral alert onanuary (General Westmoreland's actions resulting from the attacks inhe previousnd during the course of the dav began to receive more specific information that Saigon was to bethat night. In most ARVN units in III Corps the tro.ops appear to have been in their normal Tet

In IV CTZ, the nature and extent of the enemy's attacks were almost tota;iv unpx-ected.corces were aware that Viet Cong canabilitiea had improved. An NSA report ofanuary, which warned of the possibility of impending attacks in other areas, noted that units in the "Nam Bohich includes the Delta, might also be involved. The supply of modern weapons had increased and the vc had shown an ability toeries ofattacks throughout the Delta. To some degree however, this could be interpretedore aggressive allied posture in the area. In the Delta cities the presence of the VC during Tet was so traditional as to be accepted

as routine. General Eckhardt, Senior Adviser, stated that the only warning he received was General Westmoreland's alerting message ofanuary. Eckhardt was able to alert the US support and logistic units in the Delta, but was unable in the time available to restore the readiness of ARVN units. ARVN Corps commander and his threecommanders were present at their headcuarters when the offensive struck, but their units "were far below strength.

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