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June 22, 2015
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September 28, 2009
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July 7, 1970
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r. APPROVED FOR RELEASED DATE: 16-Sep-2009- THE CLANDESTINE INTRODUCTION OF NUCLEAR WEAPONS INTO THE US THE PROBLEM To assess the capabilities of foreign nations to introduce nuclear weapons clandestinely into the US, and to estimate the likelihood of such introduction over the next few years.' THE ESTIMATE I. INTRODUCTION 1. In considering the clandestine introduction of nuclear weapons into the US, leaders of any nation would have to weigh any possible advantages against the grave consequences which would follow from discovery. Despite all pre- cautions there would always be risk of detection arising not only from US security measures, but also from the chance of US penetration of the clandestine apparatus, the defection of an agent, or sheer accident. The enemy leaders would almost certainly judge that use of this tactic would be regarded by the US as a warlike act, if not as a cause for war, and that it would precipitate an international political crisis of the first magnitude. 2. We believe, therefore, that no nation would consider this course except possibly in the context of planning an attack on the US, of deterring the US from an attack on itself, or conceivably as an act of deception designed to embroil the US with a third power. It is inconceivable to us that any nation would plan an attack which relied on the clandestine introduction of sufficient quantities of nuclear weapons to have a decisive effect on the outcome of a war. Any plans for their use, we believe, would envision the use of limited quantities to achieve results unattainable by other means. 1 This estimate supersedes only that portion of NIE 4-68, "The Clandestine Introduction of Weapons of Mass Destruction into the US," dated 13 June 1968714,21 BUCHE which pertains to nuclear weapons. The judgments in NIE 4-68 regarc ing the clandestine introduction of other weapons of mass destruction are considered to be still valid. TS 190512 2 3. Only four foreign nations?the USSR, the UK, France, and Communist China?have developed and tested nuclear weapons. Beyond these, only India and Israel may do so over the next several years. We can foresee no changes in the world situation so radical as to motivate the UK, France, or any of the potential nuclear powers to attempt to clandestinely introduce nuclear weapons into the US. For this reason, the balance of this discussion will be concerned only with the remaining nuclear powers, the Soviet Union and Communist China. II. SOVIET AND CHINESE CAPABILITIES 4. Both the USSR and Communist China can _produce nuclear weapons which could be adapted for clandestine introduction into the US. We estimate that the Soviets have a broad spectrum of weapons ranging from 150 pounds in weight and yielding .25-15 KT up to very large ones having yields of many megatons and weighing thousands of pounds. Current Chinese weapons are probably fairly large and would probably require more detailed assembly and check out after being brought in than would Soviet designs. The Chinese have introduced plutonium into their weapon design and could have a composite weapon weighing about 1,200 pounds with a yield of 50 KT; they could have a weapon in the megaton range weighing about 3,000 pounds. To date the Chinese have not to our knowledge tested a gun-assembly weapon. With their present technology they could develop one yielding about 20 KT and weigh- ing 500-1,000 pounds but because of the heavy requirements of such weapons for U-235, they probably will not do so. 5. Nuclear weapons with weights of up to a few thousand pounds could be brought across US borders by common means of transport without gire-a?t-diffi- ____ culty but not without some risk. The difficulties ?and risks of introducing larger weapons into the US, even in a disassembled state, are probably sufficiently great to seriously discourage such attempts. Such devices could be carried in by fishing boats or similar small craft to which transfer had been made at sea. Any weapon could be brought into US waters in merchant ships and detonated without removal from the ship. 6. Soviet capabilities to introduce nuclear weapons secretly are much greater than Chinese. We believe that if either country undertook such a program, they would rely on their own agent organizations rather than on political sympathizers in the US. Soviet intelligence services have assigned a high priority to the development of espionage and sabotage capabilities in the US and presumably have formed an organization for the latter purpose. Should the Soviets undertake the clandestine introduction of nuclear weapons, they almost certainly would employ the highly trained and reliable agents of these services. They could also employ diplomatic personnel and could bring in weapons or weapon com- ponents under diplomatic cover. The large diplomatic establishments in Canada and Mexico could serve as bases for the operation. TS 190512 3 7. There are no Chinese Communist diplomatic establishments in the US, Canada, or Mexico. Their absence precludes the use of diplomatic cover for the clandestine introduction of nuclear weapons or their components and the use of secure diplomatic communications for planning and control of such an operation; it also makes more difficult the introduction and control of agents. Nevertheless, the Chinese could introduce agents under the guise of bona fide immigrants. 8. In considering Soviet and Chinese capabilities, we have also considered the possibility that a third country might assist the USSR or China in the clan- destine introduction of nuclear weapons into the US. We consider this highly unlikely on two counts. We doubt that either the Soviets or the Chinese would seek to enlist the aid of another nation in such a sensitive undertaking. And if they should, that nation's leaders would almost certainly react unfavorably to a proposal that could jeopardize their national survival merely to support Soviet or Chinese policy. III. STRATEGIC CONSIDERATIONS 9. If the Soviets or Communist Chinese have considered the clandestine intro- duction of nuclear weapons into the US, they have almost certainly been in- fluenced by the same general considerations: the element of risk, the oppor- tunities for clandestine introduction, and the results that could be achieved. The two countries, however, occupy vastly different strategic positions vis-a-vis the US. The Soviets and Chinese, therefore, might see the clandestine introduction of nuclear weapons in a somewhat different light. 10. 22.E.ILS,M,. The Soviet leaders, like those of the US, must take account of the possibility of general war in their military planning. In such planning, the Soviets would consider the clandestine introduction of nuclear weapons into the US, if at all, only as a supplement to the main attack by their large strategic attack forces. Because they have already achieved an assured retaliatory capabil- ity, they would probably consider a clandestine emplacement effort as poten- tially useful only in support of a deliberate or pre-emptive Soviet attack and directed toward delaying or reducing a US retaliatory attack. Possible targets might include important government headquarters, key military command and control facilities, missile detection and tracking radars, and possibly some alert forces. The Soviets would recognize, however, that even if such an effort were successful, it Sretaliatinor reduce it to what they would consider an acceptable level. 11. In considering clandestine attack as a supplement to other weapons, the Soviets would have to weigh their ability to initiate such attack rapidly, with little preparation, and in close coordination with the main weight of attack. Thus, in a preplanned attack clandestinely introduced weapons would have to be in position at the time the attack was launched. In the case of a pre-emptive IS 190512 4 attack the circumstances would not allow sufficient time for the introduction and delivery of such weapons after a decision to pre-empt. To prepare for this contingency beforehand, the Soviets would have to accept the risk of maintain- ing weapons in the US for an indefinite period of time. These difficulties would not obtain if the USSR decided deliberately to initiate general war in a period of low tension; weapons could be introduced into the US a relatively short time before use. But the Soviets would have to consider the risk of jeopardizing the element of surprise on which this course of action relies, and that discovery would have severe and up_predictable repercussions, possibly including a US pre-emptive attack which would be disastrous for the USSR. For these reasons, we think it highly unlike l fl,xItaskU?,?R will attempt to introduce nuclear weapons clandestinely into the US. 12. Communist China. The Chinese haveia.2._...c1221_33ilit7.. at present to attack the US with nuclear weapons. They probably have an ICBM system in the early stages of development, which could become operational several years from now. In the interim, they might see some advantages in clandestinely intro- ducing and emplacing nuclear weapons in the US. Inasmuch as they could not deliver such an attack on a scale sufficient to achieve a decisive military objec- tive, their object would presumably be to deter the US from a course of action that gravely threatened their national security. Consequently, the most likely targets would be population centers. 13. Clearly, the Chinese would also see grave disadvantages in such a move. So long as the US was unaware of their existence, the concealed weapons would have no effect upon its actions. Indeed, the risk of their discovery would be an ever-present, continuing danger to the Chinese themselves. Once the Chinese announced that nuclear weapons were emplaced in the US, the announcement would touch off an intensive search and extraordinary security measures. More- over, the Chinese c?qakipat_bLA,ure,..tJaatlh_e_LJS_woutd_in fact be deterred. On the one hand, the US might consider such an unverified announcement as a mere bluff. On the other it might take the clandestine introduction of such weapons as a casus belli and, having taken such actions as it could to safeguard its popu- lation, launch a devastating nuclear attack on China. In any case, the US would almost certainly seek to render the clandestinely introduced weapons unusable by threatening and preparing to deliver a devastating retaliatory attack in the event of their use. It is conceivable that some Chinese regime might be willing to accept such risks of national destruction, but we think it highly unlikely,. 14. Finally it is conceivable that the Chinese Communists might seek to intro- duce into the US a nuclear device with the intention of detonating it under certain circumstances?i.e., in a period of great tension between the US and the USSR? in hopes that it would lead US authorities to conclude that the action had been perpetrated by the Soviets. Alternatively, the Chinese Communists might think it worthwhile to introduce into the US a nuclear device so constructed as to IS 190512 5 appear to be of Soviet origin, and intended not to be detonated but to be dis- covered by US authorities. In the first case, the purpose would be to touch off a war; in the second, it would be to produce a serious crisis between the US and the USSR?a crisis which could serve Chinese interests. But it is unlikely that either deception would succeed; the procedures would be subject to most of the other difficulties discussed above, and we consider it h,lEa.1!.L_x.__._cd that the Chinese would attempt either. ?TS 190512 -a: Director a Intelligence:,519 Research, . ?,....., , ,..?, .,.... ' b.: DireCtor,'DeferiSe'lritelljgence,. enc ? , ? . . .? ? . , ,.. : ...Defense': and thill-2;.*garillatiOn '-:`64 'the Joint hiefs of. C. Assistant Chief ::'O' ,4ttiff.:,-: for Intelligence, , ...,,, , ., ? Deptiolinoro.:iif'the Army d. Assistant Chief of Naval Operations(Intelligence), Nejyy , e., Assistant Chief , pfce .7'1: f. Director of :Intelligence, AEC, for the Atomic Energy Con 6. Assistant Director, FBI, for the Federal Bureau of Investig ? Ii. Director of NSak.',,,for:,,the:.-t5latiOna -Security Agency i. Director of National Estimates, - . . :. , ,. v 2. This ument -gnay :10e':`-,retained,:. Or :destroyed burningii _ applicable securigulattensier,-,returried=.:-.1.e`4, -iTijnitelli arrangement with the 0 NatiOrtal-'*itteidteS . . , . 3. When this document '.0.Yersedoversei 'retain ' it ,ler. a period not an-',fs'excess-;'-.0 .-,-0, ' document should either be destroyed,, returned : mission --.Shiiiiid be requested of ih;lOi,.\:iiiiii? IAC?D-69/2, 22 ,.11..ii.4 :195 ., ,.. , 'i-4. The title of :.this document when used separately from the te. : sified: ENT!'