In September 1951 two classic Korean War/Stalin-era National Intelligence
Estimates were issued that might help clarify the concerns of intelligence
leaders at the time. The first, NIE-31, "Soviet Capabilities For Clandestine
Attack Against The US With Weapons Of Mass Destruction And The Vulnerability
Of The US To Such Attack (mid-1951 to mid 1952)" (Top Secret) was issued
September 4. The second, SE-10, "SPECIAL ESTIMATE: Soviet Capabilities
For A Surprise Attack On The Continental United States Before July 1952,"
(Top Secret) was published 15 September 1951, almost simultaneous with
the Ft Monmouth UFO incidents.
"The intelligence organizations of the Departments of State, the Army,
the Navy, the Air Force, the Joint Staff, the Federal Bureau of Investigation,
the Atomic Energy Commission, and representatives of the Coast Guard,
the Department of Agriculture, the Bureau of Customs, and the Public Health
Service participated in this estimate. All members of the Intelligence
Advisory Committee concurred in this estimate on 30 August.
To estimate for the period mid-1951 to mid-1952 the vulnerability of
the US to Soviet clandestine attack with weapons of mass destruction prior
to or concurrent with the outbreak of hostilities on the basis of Soviet
capabilities or such attack and US capabilities for detecting and preventing
1. The Soviets have substantial capabilities for the employment of
atomic, chemical, and biological weapons for clandestine attack upon the
2. The US is vulnerable to such clandestine attack because existing
and presently planned security measures do not provide adequate assurance
that certain methods of clandestine attack would be detected and prevented.
3. In a clandestine attack on the US the USSR would probably attempt
simultaneous delivery of a number of atomic weapons, possibly by several
a. The most likely method of attack, because the most feasible and
potentially most effective, would be the used of disguised TU-4 aircraft
[Soviet copies of US B-29 bombers almost identical in appearance to the
US model - JC] to deliver atomic weapons to a number of targets simultaneously
as the initial act of general hostilities.
b. The delivery of atomic weapons into key harbors by merchant ships
is feasible and therefore constitutes a serious threat.
d. The launching of guided missiles with atomic warheads from merchant
ships or submarines against near-coastal targets is a possibility.....
Delivery By Disguised Aircraft
16. Because of its resemblance to the US B-29, the Soviet TU-4 could
be disguised with US markings and employed for clandestine delivery of
atomic bombs. Flying a one-way mission, the TU-4 has sufficient range
to reach every important target in the US and the USSR has an adequate
number of TU-4s and trained crews to perform such missions.
17. Present flight regulations of the Civil Aeronautics Administration
and the military services require that both military and civilian aircraft
follow a previously filed flight plan and enter the US by specified routes.
Aircraft violating these requirements, if detected by our radar screen
or other means, are intercepted in flight by USAF fighters. Our radar
screen now covers Alaska and the northeastern portion of the US, and is
being extended to cover significant gaps.
18. A small number of disguised TU-4s, by taking advantage of the gaps
in our radar screen, might escape detection. This would greatly increase
the probability of a successful attack on high priority targets, such
as the Washington area, for the purpose of paralyzing the top military
and civil command a few hours prior to the initiation of hostilities elsewhere.
19. The USSR also could undertake clandestine attack with civilian
aircraft of a type used by US or foreign transoceanic airlines. Such aircraft
would have a greater chance of escaping detection and identification inasmuch
as civilian aircraft are not equipped with IFF [coded radio identification
gear - JC]. However, employment of civilian aircraft is less probable
since, at present, neither the the USSR nor any of the Satellites are
known to possess suitable aircraft, and acquisition from either a US or
foreign concern would increase the risk of compromising the operation."
Top Secret Special Estimate 10, "Soviet Capabilities For A Surprise
Attack On The Continental United States Before July 1952" is even more
intriguing, however. To quote:
" The intelligence organizations of the Departments of State, the Army,
the Navy, the Air Force, and the Joint Staff participated with the Central
Intelligence Agency in producing the section of this estimate covering
Direct Military Attack....The section on Clandestine Attack with Weapons
of Mass Destruction...is based on NIE-31....The section on Subversive
Operations, Sabotage and Civil Disturbances...was prepared by and has
the approval of the Interdepartmental Intelligence Conference. The members
of the Intelligence Advisory Committee concurred in this estimate on 10
To estimate Soviet capabilities for weakening, disrupting or destroying
the war potential of the United States by a surprise attack against the
Continental United States before July 1952.
For the purpose of this estimate it is assumed that:
a. A Soviet surprise attack on the US would be designed to cause the
maximum possible reduction in the capability of the US to wage offensive
b. The scale and nature of the Soviet effort against the US would not
be significantly affected by possible simultaneous Soviet military campaigns
in other areas.
c. The USSR would not avoid employing any weapon and tactic because
of US capabilities for retaliation in kind....
1. Atomic bombardment with long-range aircraft is the most effective
among the various types of potential surprise air operations against the
US within Soviet capabilities during the period considered in this estimate.
2. Other possible types of surprise air attack, such as conventional
bombing with high explosives, guided missiles launched from Soviet-controlled
territory and the employment of free balloons will not constitute a serious
threat during the period of this estimate. Although chemical and biological
weapons might be delivered by long-range aircraft, these weapons are better
suited to clandestine or sabotage attack. It is considered unlikely that
the USSR will possess a hydrogen bomb during the period of this estimate.
SUBVERSIVE OPERATIONS, SABOTAGE, AND CIVIL DISTURBANCES
[footnote: "The following estimate has been made by the Interdepartmental
Intelligence Conference composed of the Directors of the Federal Bureau
of Investigation; G-2, Army; Office of Naval intelligence; and Office
of Special Investigation, Air Force."]
Groups and Individuals Available for Soviet Subversive Purposes
34. To aid in its attempts to disrupt and frustrate our defensive and
counter-offensive efforts in the circumstances of a surprise attack, the
USSR has a very formidable ally within our own camp: the Communist Party,
USA. The members of that organization, now estimated at 37,000, by virtue
of their total devotion to the principles of Marxism-Leninism and to the
Soviet 'fatherland,' are committed to defend the USSR 'unswervingly,'
with all means at their disposal and at any price.
Communist Organizational Tactics in the Present Period
37. The Communist Party, USA, has always conducted some of its activities
on an underground basis, but since 1947, that basis had been enlarged
considerably through the taking of elaborate 'security measures' designed
to provide additional cover for its activities. Now, since the indictment
of the National Board members (17 June 1948)...the Party has gone even
further underground. A Soviet surprise attack would surely complete the
Communist Action to be Anticipated in Event of Soviet Surprise Attack
40. In the event of a surprise attack, the Communist Apparatus may
be expected to make coordinated attempts immediately to destroy:
a. our will to resist
b. our means of resisting
41. Psychological warfare directed toward the destruction of our will
to resist (or toward causing fatal hesitation or confusion in repelling
the attack and launching the counter-offensive) might take the form of
widespread circulation (effected, e.g., through newspapers with 'forged'
mastheads and titles, broadcasts over seized radio stations, etc.) of
false reports and rumors concerning: the strengths and initial successes
of the enemy; the destruction and/or capture of important cities; the
slaughter of millions of military and civilian citizens by means of both
powerful and insidious weapons; the surrender of important units of our
Armed Forces; the existence of total confusion among our military and
Government leaders; and the unmasking (forced or spontaneous) of Communists
in high military and
Government posts. Such efforts, if successful, might cause seriously disruptive
civil disturbances, such as race riots, a revolutionary situation on the
home front, and a lowering of military and civilian morale."