NATIONAL INTELLIGENCE ESTIMATE NUMBER It-5
PROBABLE INTELLIGENCE WARNING OF SOVIET ATTACK ON THE US THROUGH
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DIRECTOR OF CKNTMArloltoving intelligencearti-ipoted in Ihii ettimatt. Tho Ctiiiral IntelUgencetheir;<int atcartmentstie Army. UU .lit,Air Far(r. Thr 'vmt Sftf,IWrflVl rhe ft'lona! Securitybfadvisory:s ji,
ligfce. Dcvulm- -iSfofa.l; theeerorftata!the DireeU* ofUF. flir Deputy Director for Intditgcict.Mnergy Com-miMlonhe IAC. The A'Ostant to the Director, Federal Bureoui* tligit'.m. nb.fomai. the tub-
iect bring ouUi.lv Of In furwtXtion.
CENTRAL INTELLIGENCE AGENCY
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PROBABLE INTELLIGENCE WARNING OF SOVIET ATTACK ON THE US THROUGH
To estimate the probable degree of advance warning that could be provided byin the event of Soviet attacks on the United States and key US installations and forces overseas through
NATURE OF WARNING
When discussing the advance warning of Soviet attack which intelligence may be able to provide, it is necessary to define various possible kinds of warriing:
Warning of the increased likelihood of war, probably resulting either fromactions or Soviet reactions to Western actions, but not necessarily involving any direct military aspect;
Warning of increasing Soviet military readiness to attack, but withoutevidence of Intent to attack or of the time of attack;
Warning of clear intent to attack;
Warning of clear intent to attack at orarticular time.
It seems improbable that stager possibly even stageould be reachedexcept in the event of high level penetration of the Soviet command, whichseems unlikely, or in case of some exceptional intelligence bonus or breakthrough. While intelligence might be able to say that the USSR would be fully prepared towithin, sayays, it would find it very difficult to say whetherirm intent to attack, were primarily in anticipation of an expected US attack,eception maneuver, or were to prepare against any contingency. When we speak of degree of warning, therefore, it is important to bear in mind that both time and specificity are involved, and that the earlier the warning the lessit is likely to be. This inverse relation between time and specificity is anlimitation of the warning function.
tbc Soviet attack on the US would beto general war, this estimate also deals with the over-all warning which the OS would be likely to receive of Soviet InlUaUon of general
war. It docs not consider the warning UKely to be given by US or allied early-warning radar, nor the warning which could be obtainedoviet ultimatum, since such warning isthe scope of the problem.
Tbe (act that warning is likely to be in some degree imprecise or contingentincreased importance to other considerations affecting the warningthe nature and degree of warning which can be obtained will always beon many complex factors, some of them unique to any given set ofWarning will depend first of all on maximum alertnessaximumcontinuous effort by intelligence. These would probably be maintained onlyperiod of rising tension and might be reduced, even unwittingly, li theto rise, if there were intermittent periods of apparently declining danger, orhad previously given false warnings. The effectiveness of warningon the continued credibility of intelligence warnings to responsiblewarningrocess is complete only when it is acted upon. The warningis thus affected by the whole context of events in which it operates,factors and even pure chance. It cannot be regarded as awhich it is possible for intelligence to set up once and for all and whichoperates
Wc beUeveoviet initiation of general war by attacks on the US, Itsor key overseas installations would almost certainly be preceded bypolitical tension. While suchwould in itself constitute warning that war was becoming more likely, the indications of Soviet preparations which would probably be obtained could beas evidence of preparations for defense or as partar of nerves. Therefore. Soviet behavioreriod of heightened political tension would not necessarily give specific warning of aintention to attack. Nevertheless, intelligence could probably give warning of the USSR's increasing war readiness and could probably chart thc trenda period of maximum
2 It would also be possible for the Soviet leaders,eriod of prolongedin which they had brought both their political and military preparations to an advanced stage, to bring about an
amelioration of thc crisis atmosphereeception move.ove, while involving sacrifice of some advantages, would almosi certainly be made if the Soviet leaders considered that adegree of surprise was essential to their strategic plans. Alliedhowever, might still be able tothe continuation of specific military preparations which would be particularly significant as evidenceovietto achieve surprise in launchingwar. )
f the USSR chose to initiate war with full-scale land, naval, and air attacksa period of mobilization, there would be numerous indications of military, as well as of economic and politicalnecessary to prepare such attacks. We believe that US Intelligence might be able toeneralized degree ofas long as four or possibly even six months prioray, and that theperiod would not be less than 30
days.0 thc number ofwould probably be reduced due to Soviet security measures, although the latter would themselves provide warning.nd, there would probably be certain indications of last-minute preparations, althoughand disseminating theseimely basis would probably be difficult. As the time of attack drew near,of its approach would becomespecific. Based on observed Soviet military activities, warning could probably be givenew hoursew days in advance of the actualof the attack. )
In order to gain some degree ofthe USSR might choose to initiate general war by attacks of less than full scale in Europe, the Middle Fast, or in the Far East directly or through the Chinese Communists, while simultaneouslythe US and key overseasThe degree of prior Sovietwould vary greatly, depending on the location of the attack and theand direction of the preceding polilical tensions. Even so, thepreparations which the USSR would have to take to put its forcestate of readiness to attack, and tosupport after the attack began would probably require aboutays. Wethat warning of the probability of attack could be given about one week in advance, but the period might varyew hours to as much asays,on the seasonal pattern ofmilitary activity. )
We have estimated inhat by exercising its maximum capabilily the USSR could now launchomb-
er aircraft against tbe US in an initial attack. However, virtually all of these aircraft would be medium bomber types (BULLS andew would be heavy bombers (BISONS andhc great bulk would have to fly one-way missions. At present, Soviet preparatory activities for maximum scale attack would require at least several months, and probably considerably longer, and would probably become known to alliedespecially if carried forward with great urgency. We believe that thewould probably assume apattern in time for intelligence toeneralized degree ofays prior to attack. US intelligence would also be likely to discover significant activities indicating the movement of the large numbers of aircraft to staging bases involved inaximum scale attack. Wc believe that intelligence could give specific advance warning ofand possibly threatening airon the order)
e have estimated, inhat ii the USSRurprise attack against the USircraft would probably be launched fromvailable staging bases in the Kola,and Kamchatkahereack of sufficient evidence to permit
and In paragraphs.arning given in hours Is defined as the elapsed time Between the receipt of uitormaUonS command or agency having authority to alert US defeases) which Indicates threatossible Imminent Soviet aU atuck. and the time such an attack would reach Uie existing continental) and the'proposed (DEW) line
a full discussion or these forward bases, see NIK, "Soviet Oron CapabiliUes foron the US and Key Overseas InslallaUons and Forces"
firrn assessment of the capabilities of'.dividual bases in these areas for staging bomber aircraft. However, we believe thatajor effort the USSR could launchircraft on Initial attack against the US. Preparations for such an attack would permit possibleby allied intelligence and, ifwouldeneralizedof warning of several days, andadvance warning of unusual and possibly threatening air activity on the orderours.educed scale of attack,ircraft could be launched against the US and,by an extraordinary security effort, might be launched5 with little or no specific advance warning to USThis estimate rests on thcthat the forward bases may now be capable of handling these aircraft or may become so without detectable
8 the bases, training, andof the Soviet Long-Range Air Force could,ajor effort, be advancedoint where only minimumwould be required prior to aattack which could then numberomber aircraft. Provided thatajor effort has been made, movements in and out of the forward staging bases may also become routine. The likelihood that these movements would be discovered would not be much less than at present, but the difficulty of assessing them as warning indicators would thus be very muchhe increased speeds of jet bombers will reduce the time required for movement to staging bases and theincreased handling capabilities at
the bases will reduce time requiredand servicing.specific advance warning ofpossibly threatening aircould be given, assumingto the staging bases wasand correctly interpreted,be on the order
at present andfto staging bases was notwarning could be obtainedalmost continuous reconnaissancestaging areas was beingaircraft were discovered afteralready reached these areas.reliance on this means alonethc warning periodeweven virtually to zero, because ofdifficulties and delays ininterpreting the results of the
thc period of this estimatewillrogressivelyfor launching one-waythe US from interior Sovietwould probably provide nowarning to USthere are two other waysthe USSR might8 (andsomewhat before that year) launch
' The Director of Intelligence, USAF. believes thai movement In and out of forward staging bases mar become routine8 If currentlyrfforU to improve the bases, training, and equipment of the Long-Range Air ForceHe alsonlikely that such movement would be discovered and correctlybefore Its value as warning had passed Moreover, the Increased capability ot the Sovicl Union to launch heavy bombers from interior bases will further dcgindc Ihis source of warning InformaUon.
"For full discussion of Soviel long raneesee Nrrs. -Soviet Oross CapablU-Ues for Attacks on the DS and Key Overseas lo-st* nations and Forcesuly ISM"
an attack on the US inay that no specific warning would be likelyits actual launching:
a. Assuming that the USSR pressed ahead with development of its advance bases in the Chukotski, Kamchatka, and Kola areas, and with the generalof its Long-Range Air Force, "normal" nights of aircraft to and from these bases would almost certainly occur In increasing number as the development of the basesattern ofwould thus tend to be established. Under these circumstances, anumber of aircraftthe number engaging in such "normal"would almost certainly be able to take off from these bases (and those in the Leningrad area)urprise attack upon the US without any such unusual prior preparations or assembly as would particularly attract the attention ofintelligence.
urning that the USSR acquires an inflight refueling capability (which it can do although there is no evidence at present that the Soviet Long-Range Air Force possessesapability) and develops it to the necessary degree, Soviet heavy bombers could also be launched on two-way missions from certain home bases without specific advance warning, and without staging at the advance bases.*
f the USSR, concurrently with any of the scales of attack discussed above, undertook submarine operations against
"Only the BEARith Itsestimated characteristics, could reach allin the US. See.
the US and key overseas installations, it would be necessary for Hie submarines so employed to proceed to wartime patrol stations shortly before the expectedof hostilities. The passage of these submarines might give up to two weeks warning of Soviet preparation for attack. If the USSR undertookraider operations with some of the major units of their surface fleet against allied lines of communication, theof these raiders might give up toays warning of preparation for attack. )
oviet preparations to receive ablow from allied air power could probably provide some indication ofintent to attack. Minimumwould probably include the alerting of air defense forces and the civil defense organization, preparations of military units and installations for air defense, the dispatching of submarinesby increased aerial reconnaissance to locate US carrier forces, and theof key personnel and possiblyof population from potential target areas. If steps such as these were taken, they would probablyarning period of as mucheek toays, and, taken in conjunction with otherwould greatly increase the defi-niteness of any warning US intelligence might be able to give. We believe that in elementary prudence the USSR would be unwilling to forego preparation toetaliatory blow; therefore, someindicators of this type would probably be obtained.
WARNING FROM SOVIET BEHAVIOR IN VARIOUS CIRCUMSTANCES
he various possible circumslances in which tbe USSR might decide to attack the US and enter upon general wor wouldonsiderable bearing on the degree of warning which might be obtained.
are three situations ln whichmight deliberately decide to atlackand key overseas installations, thusgeneral war. These situationsIf the Soviet leaders came to believe:the USSR had acquired such militarythat It could be certain of successgeneralhat the US and itsplanning an attack on the USSRthe USSR's only hope of survival laythe Initiative;hat anshift In the relative weight ofwas Impending which wouldthe USSR to choose between certainin war and sacrifice of lis vitalbelieve that the Soviet leaders arecome to any of these conclusionsperiod of this estimate.
remains the possibility Uiatwar might occureries ofcounteractions in some local crisisthc USSR nor the Western AlliesIntended to lead to general war.USSR believed that the Issues atvital to Its security or Uiat lhe lossInvolved In backing down woulddangerous to Soviet power, and ifUiat Uie US would not yield, thenmight decide Uiat genera) war wasconsequence of thc crisisIt should seize the initiative. Wethat if Uie USSR decides to launchwar In Uie period throughs most likely to come as theofituation.*
'The Soviet altitudes toward general war referred to in paragraphre discussed more. "Soviet Capabilities and Probable Courses of AcUon" datedections VI and VII.
ikelihooderiod of Tension. In the situation described under b. above, adecision to attack the US woulderiod of heightened tension. Moreover, even If Uie Soviet leaders reached any one of Uie three conclusions In a. above, they would probably do so because of anshift in International "alignments, or because of some equally open and markedor Impending alteration, of Uieweight of military power. Suchwould themselves be likely to produce heightened political tension. There arehowever. Inoviet decision for war could be taken in Uie absence of pollUcal tension. Foroviet decisionas underbove might be theof some technical advance in Sovietcapabilities unknown to Uieoviet decision motivated asbove might be Uie result of some secret technical advance In Western militaryof which Soviet intelligence learned. We believe that such situations are unlikely to arise. Therefore, since an attack on the US. if it occurs, is most likely to arisecries of actions and counteracUons not originally Intended to lead to general war (paragraph. it would almost certainly be precedederiod of heightenedeliability of Political Indicatorseriod of Tension. While the existencerior period of tension would in itselfwarning that war was becoming more likely, It would also greaUy increase thcof obtaining from Soviet politicala specific warning of attack. Most of thc political actions taken by the USSReriod of war preparation might not diner greatly from those undertaken asln any period of heightened political These actions might include:approaches to some .states designed to influence them toward abandonment of their alliances with Uie US; massive "peace"directed al the populations of Western states and intended to undermine the will to resist or to destroy confidence In the motives
and Intentions of governments; explicit threats against would-be aggressors; newto ban nuclear weapons; Instructions to Communist parties to ready themselves for their sabotage and subversion missions;propaganda directed to the Blocto prepare them psychologically for "resistance toll such actions, however, could be Interpreted as defensively motivated or as partar of nerves. Thus while they might provide warning of thelikelihood of general war, they would not provide specific warning of attack.
Reliability of Military Indicators; in aot Tension. The existenceeriod of heightened tension would also make morethe determination from Soviet military preparationspecific Intent to attack. If Ineriod the USSR undertookmilitary preparations, It would probably be as difficult to distinguish offensive from defensive Intent as in the case of Indicators from Soviet political behavior. In asituation of this sort intelligence probably could only give warning of the USSR'swar readiness and chart the trend toward the period or maximum danger, but not warnoviet intention to attack. The USSR might be carrying out militarynot in order to initiate war but Infor instant retaliationS attack which It feared might be impending.
Possibility o/ Soviet Deception. It would also be possible for the Soviet leaders,eriod of prolonged tension In which they had brought both their political and militaryto an advanced stage, to bring about an amelioration of the crisis atmosphereeception move. They couldasis for new negotiations, andreduction of some of their militaryor even actually reduce them. If they considered surprise essential to their plans and believed that they still could achieve some degree of surprise in theirattack, this wouldikely course for thc Soviet leaders to pursue. However,ourse would Involve sacrifice of someAn initial surprise assault aimed at Western retaliatory power might include
air attacks on the territories of some states which thc USSR might otherwise have hoped to neutralize politically, lit would probably also Involve the clear assumption offor Initiating war by aggressive action, and thus might harden the will to resist ln some Western countries. Nevertheless, the Soviet leaders would almost certainly accept these disadvantages and attempt deceptivemaneuvers If they considered that the maximum degree of surprise attainable was essential to their strategic plans.
arge degree of deception could be introduced Into Soviet behavior,intelligence might still be able to detect the continuation of specific militarySuch Indications could be Interpreted as due to Soviet caution and mistrust, but they would also point to the possibilityeception maneuver and they would besignificant as evidenceoviet Intention to achieve surprise in launching general war.
Summary. We believe, therefore, that Soviet behavioreriod of heightenedwould not necessarily give warning of attack. It would probably establish that Soviet readiness for general war wasit would also establish that thc likelihood of war was Increasing but would notIndicate that general war was probable. It would also lead to heightened activity and sensitivity on the part of allied Intelligence. However,elligerent and unyielding attitudeefensive and conciliatory one wouldure guide to Soviet intentions.
H. AITERNATIVE SCALES OF SOVIET ATTACK
probable degree of warning thatwould receive of Soviet attack wouldin large part upon thc type ofMany courses of action arethe Soviet planners In thc eventdecide to initiate a. general war.end of the spectrum would be aSoviet attack on thc US andundertakeneriodlan of attackstrategic surprise in favor ot maxi-
t*MM* i g
military preparation, although the USSR might still hope to achieve some degree of tactical surprise. At the other end of the spectrum wouldoviet surprise attack, with no prior preparationsature that could be relied on to provide warningSuch an attack would sacrifice weight for the advantages of surprise. This estimate does not attempt to forecast Soviet strategy or the probable scale of the initial atuck. It only discusses the probable degree of warning which would be obtained if Soviet planners selected any one of the following alternatives for their Initial attack:
campaign in Westernexisting deployments andon the US and key US overseasInstallations; .
attacks only on thc US andoverseas forces and installations
Maximum scale attack
ARNING OF FULL-SCALE SOVIET ATTACK
ull-scale attack employing all arms in strength at the outset of war wouldbe precedederiod of mobilization during which full war readiness, or aclose to it, had been achieved. The range of activities necessary for such fullof war potentialighlystate like the USSR is so extensive and Involves so many measures affecting broad sections of the population thatotalitarian government would find itto conceal all of them. Ln the economicomplex redirection andof productive effort would have to take place as materials, manpower, and facilities were transferred from consumption andgoods industries to armamentThese measures would probably be Impossible without the use of publicmedia. In addition, manipulation of domestic opinion Is so persistent aof thc Soviet government and its concern over popular morale under conditions ofis so intense that Its vast propaganda appa-
ratus would certainly be openly committed to preparing the Soviet people^ to withstand the strains of general war.
In the military field Itself, the induction of additional military classes, formation of new units and fleshlng-out of existing units to full strength. Intensified and more realistic training, redeployment of combat groups to forward areas,ariety of logisticwould hardly escape entirely theof Western Intelligence. In particular. It would be difficult for the USSR to hide large-scale troop movements ln East Germany or the other Satellites and forwardof Its naval units. Withdrawalignificant portion of civil aircraft fromflights to augment the aircraft of the airborne forces or for other purposes might give additional warning of full-scale attack. At present numerous specific preparationsull-scale air effort against the US would have to be made by the Soviet Long-Range Air Force, although byhe extent and reliability of such Indicators could be considerably reduced (see paragraphelow).
At present, if the USSR undertookull-scale aitack, US intelligence would probably receive numerous Indications of large-scale Soviet mobilizationeriod of about six months to about one monthay, largely because thelikely lo be undertaken during this period would be those least susceptible ofHowever, If the decision toto full mobilization cameeriod of prolonged tension In which preparatory measures were Initiated, or If6 general Soviet war readiness should be substantially Increased, then initial indicators mightconsiderably later than six months prioray. In any event, from0 to0 days, we would be likely to get much less In the way of indicationsthe preparations In this period would be those which Soviet security Is best equipped to conceal. Moreover, by about one monthay the progressive lightening of Soviet security measures would probably haveigh point. There would almost
certainlyeduction In information from sources within the bloc; at the same tune, however, the drying up of internal Bloc sources because of Intensified securitywould In Itself provide an Indication of Soviet preparations. Then, in the period0 andn. we could expect indications of last-minute preparations. At this time, however, there woulderious problem of processing and disseminating such indicationsufficiently timely basis.
We believe that allied Intelligence would probably be able to sort the varietyeaningful pattern at aearly stage of Soviet mobilizationull-scale attack. US Intelligence mightaware of this mobilization as long as four or possibly even six months prioray. The minimum period would probably not be less thanays. Even thoughwas able to giveeneralized degree of warning, showing the progressive increase of Soviet war readiness, It would probably still be able to chart the trend of full-scale preparations, to anticipate their probable course to completion, and thus to designate? the beginningeriod ofdanger. It might even be able to identify features of Soviet full-scalewhich because of their uniqueness or extreme costliness could be Interpretedas evidence or an Intention to attack.
As the time of attack drew near,of its possible approach would become increasingly specific. Based on observed Soviet military activities, warning couldbe givenew hoursew days in advance of the actual launching of the atlack. This would be rendered veryhowever, if Soviet forces, when their preparations for attack were known to be near completion, undertook air. naval, and ground reconnaissance, or attempted major feints. These activities might provide evidence of Soviet intention to attack, but wouldthe difficulty of determining the time of such attack. It might also be recognized that, in theory at least, the USSR couldrefrain from or delay attacking even after preparations were complete. Hence
the indications of military readiness, taken by themselves, would not necessarily provide conclusive evidence that attack was certain.
IV. PROBABLE DEGREES OF WARNING IN THE EVENT OF LESS THAN FUll-SCALE ATTACK
If the USSR were to sacrifice weight for thc advantages of surprise. It would be forced, depending upon the degree of suprise it sought, to accept certain major limitations; (a) no large-scale mobilization of additional units; (b) no large-scale redeployment ofair. naval, or ground forces, especially to forward areas; and (c) no unusual movement of Soviet air, naval, or ground forces in such areas as would be likely to indicate theof attack. However, even If the USSR attempted to achieve the utmost surprise in launching general war. it would still probablyinimum number of priora matter of necessity and elementary1 prudence. Therefore, at least some of the general preparations discussed in Section III above would almost certainly have to beSome of these preparations would be detected by allied Intelligence, but itwould be very difficult to ascertain any such clear pattern of preparations as would be discernible in event of mobilization for full-scale attack. Again, the degree ofalready achieved by Soviet forces would affect thc number of indicators obtained and the general political situation would affect the intensity of US intelligence effort and thc ability of intelligence to interpret correctly such indicators as It did obtain.we believe It possible that thesewould not leadarning ofespecially if they were carried outong period of time and with careful
If the USSR decided to attack thc US and key overseas installations without full prior mobilization for general war, and hencefull-scale attacks ln other areas, twoalternatives would be open;
a. It could combine Its attack against the US and key overseas installations with aground campaign in Europe, thc Middle
arid In Uie Far East directly or through the Chinese Communists without priorof Its forces.'
b. It could undertake initially air. andother forms of attack, against the US and key overseas Installations, but delay Its ground campaigns and discerniblefor other military operations until after these initial nttacks had been launched.
V. SOVIET CAMPAIGN IN MAJOR AREAS AND SIMULTANEOUS ATTACKS ON THE US AND KEY OVERSEAS INSTALLATIONS
f thc USSR chose to initiate general war by an attack with the forces currentlyIn Europe, the Middle East, and the Far East, together with attacks on thc US and key overseas installations, the degree of its over-all prior preparations would varydepending on the location of the attack and the intensity and duration of thepolitical tensions. If, as we think likely, there hadong period of crisis, the USSR might have already achieved adegree of military and economicfor war. and its foreign andpolitical preparation might be wellMoreover, during the, measures may be taken ostensibly or actually in response to externalest German rearmament, which would greatly Improve Soviet readiness for attack. Therefore, the Indicators derived from such activities, though warning of thc increased readiness for war and likelihood of war, would probably be of limited significance forof this type of attack. Even so, thelocal preparations which the USSR would still have to take for an attack with forces in place would provide some degree of warning.
' The XlSsn could of course strengthen this ground attack by some degree of prior reinforcement For the purpose of this estimate, however, we take thc above case as the limitingny prior reinforcement would tend to provide ad-dlUonal indicators and hence additional
Europe, for example, some timerequired to assemble major elementspositions, although- this wouldThe longest periodbe between May and August whensplit between home stationsesser period would bebetween November and Marchare consolidated at home stations;period required would be inunits are moving to training areasSeptember-October when units areln large-scale maneuvers or areback to home stations. Otherpreparations would include thestocks of transport, munitions, andin quantities well in excess of thoseon full-scale maneuvers. Intwo weeks before the attack Itbe necessary to begin thelarge numbers of locomotives andfrom East Germany to the Sovietin order to prepare for resupply andoperations to support andoffensive. Altogether, the USSRbe engaged in thesea period of aboutays and USwould probably begin to acquireat an early stage, althoughwith the season of the year. Wewarning of the probability ofbe given about one week inln the absence ol otherwith Soviet actions appearing to bea normal pattern, the warning couldfollows:
a.ew hoursew days in April and in September-October;
o. from two to five days ln November-March;
c. Irom five toays in May-August.
the USSR undertook concurrentoperations against the US andInstallations, It would bethe submarines so employed towartime patrol stations'shortly beforecommencement of hostilities.of these submarines might givetwo weeks warning of Sovietattack.
If the USSR undertook concurrent raider operations with some of the major units of their surface fleet against allied lines ofit would be necessary for the units so employed to proceed to their assigned areas of operaUons shortly before Uie expected commencement of hostilities. The movement of these raiders might give up toays warning of preparation for attack.
In addiUon, any unusual and unexplaln-able deviation from the normal operatingof the Soviet Bloc merchant marine couldupporting indicator of Sovietlo attack.
The extent to which the preparationson simultaneously for air attack on the US and key overseas Installations and forces would tend to confirm and/or advance the warning would depend somewhat upon thc planned scale or these attacks, as discussed below.
VI. INITIAL AIR ATTACKS ON THE US ANO KEY US OVERSEAS FORCES AND INSTALLATIONS
For the purposes of this estimate it is necessary to consider two types of air atlack on the US and key overseas InstallaUons:aximum effort using as many aircraft as possible, and (b) an attack designed toigh degree of surprise. The USSR could undertake these air attacks on the US and key overseas installations andull-scale attack ln Eurasia or with Uie less than full-scale attacks discussed in. Alternatively, the USSR could iniUate general war with such air attacks only, while delaying discernible preparaUons for other military operations in order to increase Uie likelihood of surprise against the US. In this case. Uie verybetween preparations for long-range air operations and those.for other genera) war campaigns couldighly significant Indicator of the probable nature of the initial Soviet attack.
Maximum Air Attack. We have estimated Iniat by exercising Itscapability the USSR could now launch
ong-range aircraft against thc US in an initialyhe maximum number launched could beto. However, wcextensive prior preparations would be required, particularly in the early part of the period covered by this estimate. These would almost certainly Include improvingmaintenance and fuel storage facilities in Uie Chukotski. Kamchatka, and Kola areas, bringing personnel and equipment to full strength ln long-range air units, probablytraining of air personnel, increased frequency of long-distance training missions, and raising levels of maintenance, andtraining ln inflight refueling tecluilques. The critical indicators would be thoseto increased levels of activity at staging bases in the Chukotski, Kamchatka, and Kola areas, since8 as well as at present these bases would be essential to maximum attacks on the US.owever, thcof Soviet dependence upon these forward areas, and thus their significance as aindicator, would decline If the USSR, as partaximum scale attack, chose to launch some or all of its heavy bombersfrom Interior bases or cither one- or two-way missions or combinations thereof. Except for the BEARven Soviet heavy bombers employing Inflight refueling would still require advanced bases for making two-way attacks on the most distant US targets.
t present, Soviet preparatory activities for maximum scale attack would require at least several months, and probablylonger, and would probably become known to allied intelligence, especially ifforward with great urgency. We believe that the Indicators associated with prepara-Uon of the advance bases, taken together with others pointing to the Increased readiness of
'The great bulk of these aircraft would have to fly one-way missions, but the problem oflearning by intelligence, as distinguished from tactical looming by* early warning radar, would not be significantly different If the USSR, In order to permit two-way missions by more of tbe strike aircraft, chose to Include someof tankers. If available, In the totalof planes launched.
Long-Range Air Force, would probablyeaningful pattern in time fortoeneralized degree ofays prior to attack.this would be warning only ofreadiness and not of Intent to attack.
If such preparations proceeded gradually over the next few years, they would have even less significance for warning, since they could well be partormal bulld-up of the USSR's long-range air capability. Thus,hc bases, training, and equipment of the Soviet Long-Range Air Force couldoint where only minimumwould be required prior to an attack. There would then need to be little in the way of movement of personnel and equipment, logistic activity, or training flights which would departormal pattern ofUnder these circumstances, indicators of the preparations taking place in the Soviet Long-Range Air Force might be few, and warning would depend almost entirely onreceived during the staging of
At present, US Intelligence would beto discover significant activities Indicating the movement of the large numbers ofto staging bases involvedaximum scale attack. Considering also the amount of time that the aircraft would require to reach such bases, together with the timefor refueling and servicing at the bases, we believe that intelligence could give specific advance warningf unusual and possibly threatening air activity on the orderours before thc attacking aircraft reached the early warning radar screen. It wouldbe possible, of course, for such atoractice maneuvereint, and therefore warning of actual intent to attack could not be given with complete certainty.
"Here and Iniven in hour terms ls defined as the elapsed Umc between thc receipt of InformaUonS command or agency having authority to alert US defense which Indicates an Imminent threat of Soviet air attack, and the Ume such an attack would reach the existing continental) and the proposed (DEW)
Developments are taking place In therSo-vlet Long-Range Air Force which probably will decrease the possibLUty-of detection, and Increase the difficulty of interpretingin terms of Intent to attack.ovements Ln and out of forward staging bases may become routine, provided thattheajor effort had beento Improve base facilities andlogistics, and equipment of the Long-Range Air Force. The likelihood that these movements would be discovered would not be much less than at present, but the difficulty of assessing them as warning Indicators would be very much greater. In addition,8 the Increased speeds of Jet bombers willthe time required for movements tobases, and the probable Increasedcapabilities at the bases will reduce time required for refueling and servicing.the specific advance warning of unusual and possibly threatening air activity which could be given, assuming thatto thc staging bases was discovered and correctly Interpreted, would probably be on the orderours."
Both at present andf theto staging bases was not discovered, warning could be obtained only if almostreconnaissance of the staging areas was being maintained and aircraft wereafter they had already reached these areas. However, reliance on this means alone might reduce the specific advance warning periodew hours, or even virtually to zero, because of possible difficulties and delays in processing and interpreting the results ofMoreover,8 the probable growth in Soviet air defenses would make such reconnaissance considerably more difficult.
"The Director of IntelUgence, USAF. believes lhal movement In and out of forward staging bases may become rouUne8 If currentlyefforts to improve the bases, training, and equipment of the Long-Range Air ForceHe also believes It unlikely that such movement would be discovered and correctlybefore its value as warning had passed. Moreover, the Increased capability of the Soviet Union to launch heavy bombers from Interior bases will further degrade this source of warning InformaUon.
The additional preparations which would be necessary to attack US overseaswould not Increase the likelihood ofadvance warning.'1 In the eventaximum scale attack, the long-range air arm would already beigh slate ofThe readying of the Jet Light bomber units which could also be used for attacks in Western Europe, the UK. and some parts of the Middle East and Far East could bewithout serious additional risk of detection unless very large numbers had to be deployed to forward bases. If guidedwere employed, no warning of their use would be obtained, apart from thewarning which might have been derived from prior preparations for hostilities.
Surprise Air Attack. However much the Soviet planners desired to achieve surprise in their initial air attacks on the US and key overseas Installations, they would still wish to achieve the optimum weight of attackwith surprise. We have estimated inhat If the USSRurprise attack against the US Inircraft would probably be launched from thevailable staging bases In the Kola,nnd Kamchatka areas. Thereack of sufficient evidence toirm assessment of thc capabilities of thebases in these Areas for staging bomber aircraft. However, we believeajorthe USSR could launchircraft on initial attacks against the US.for such an attack would permit possible detection by allied intelligence and, if detect-
"Although variations In the relative priority as to timing and weight of attack between the US and overseas Installations would not alfect the advance learning obtained by Intelligence, ther would be of great significance for the tactical teaming derived from radar due lo the varying times at which aircraft bound for targets atdistances would be picked up ForIf the USSR chose lo make atlacks oo
overseas InsiallaUons before launching attacks oa the US itself, those attacks would alert thc
continental US defense system, allhoueh the
overseas Installation* mlvhl obtain only radar warning of the attack They would piobably have been alerted, to some extent, however, by
generalised warning derived from general piep-
aratlons for hosUllllcs
ed, wouldeneralized degree, of warning of several days, and specific advance warning of unusual and possibly threatening air activity on the orderours.
educed scale of attack,ircraft could be launched againsi the US, and accompanied by ansecurity effort, might be launched Inith little or no specific advance warning to US Intelligence. This estimate rests on the belief that lhe forward bases may now be capable of handling these aircraft or may become so without detectable
As estimated In paragraphs8 the USSR could, provided forward base construction, training, and equipment of tht Soviet Long-Range Air Force weredeveloped, launch Its maximum air attack ofircraft against lhc US under such conditions that the period of specificwarning of unusual and possiblyair activity would probably be on the orderours, and might beless If the movement to staging bases was not discovered. Thus8 theSoviet air attack, provided no othe: waxning of Soviet intent to go to war had been received, couldigh degree of
During the period of this estimate the USSR willrogressively increasing capability of launching one-way atlacks on the US from Interior Soviet bases which would probably provide no specific advance warning to USoreover, there are two other ways in which Uie USSR might8 (and possibly somewhat before that year) launch an aluiek on thc US Inay lhat no specific warning would be likely before Its actual launching:
c. Assuming that the USSR pressed ahead with development of Its advance bases in the Chukotski. Kamchatka, and Kola areas, and with the general preparation of its Long-Range Air Force. 'Tiormal'- flights of aircraft to and from these bases would almostoccur in increasing number as the develop-
"For full discussion of Soviet long-rangeseeS5.
merit of thc basesattern of activity would tend to be established.theseonsiderableof aircraftroughly the numberIn such "normal" activityalmost certainly be able to take off from these bases
(and from those in the Leningrad area)urprise attack upon the US without any such unusual prior preparations or assembly as would particularly attract the attention of allied intelligence.
b. Assuming that the USSR acquires anrefueling capability (which it can do although there is no evidence at present that the Soviet Lung-Range Air Force possessesapability) and develops It to the necessary degree, Soviet heavy bombers could also be launched on two-way missions from certain home bases without specific advance warning, and without staging at the advance bases."
VII. WARNING FROM SOVIETTO RECEIVE RETALIATORY ATTACKS
n important element not included in thc foregoing examination Is that of Sovietpreparations toetaliatory blow
" "Only thc BEARith Itsestimated characteristics, could reach all tari-cU In the US. Sec
from allied power. Minimum preparations would probably Include the alerting of air defense forces and the civil defensepreparations of military units andfor air defense, the dispatching of submarines accompanied by Increased aerial reconnaissance to locate US carrier forces, and the evacuation of key personnel andsegments of population from potential target areas. If steps such as these were not taken, they would constitute seriouson thc USSR's ability toetaliatory blow. If they were taken, they would probablyarning period of as mucheek toays, and, taken in conjunction with other Indicators, would greatly increase the definlteness of anyUS Intelligence might be able to give. The risk which the USSR would be willing to acceptesult of neglecting some or all of this type of defensive preparation would depend in part on thc degree of success which the Soviet leaders expected their own initial attack to achieve. We believe that inprudence they would be unwilling to forego preparation toetaliatory blow; therefore, some Important indicators of this type would probably be obtained.Original document.