1. To determine the military implications of weapons employing thermonuclear
reactions in deuterium and tritium to obtain energy releases in the order of
millions of tons of TNT.
2. That it is within the capabilities of the United States from the
standpoint of money, materials and industrial effort to develop for test of
feasibility a prototype thermonuclear weapon.
3. If the thermonuclear reaction of light elements were proved feasible of
attainment, that it would be within the capabilities of the United States to
produce these weapons in limited quantities.
4. That no practical factors are known to exist which conclusively eliminate
the possibility or probability of Soviet development of a thermonuclear
weapon in minimum quantities.
5. See Inclosure 1.
6. The United States military position with respect to the development of the
thermonuclear weapon should be:
Enclosure 1
Discussion
1. General. The term “thermonuclear weapon” as
used herein refers only to a weapon employing a thermonuclear reaction
in deuterium and tritium to obtain energy releases of millions of tons
of TNT. The term “fission weapon” refers to an atomic weapon employing
the fission of uranium isotopes or plutonium as the primary source of
energy. From the discussion of technical considerations by the Atomic
Energy Commission it appears that there is a reasonable chance that a
thermonuclear reaction of light elements can be achieved by the United
States within the next few years if a special effort in this direction
is initiated shortly. Consideration of known Soviet developments in the
field of atomic energy reveals a degree of Soviet capability also to
develop a thermonuclear weapon. The following discussion explores the
military implications of thermonuclear weapons under several hypotheses
in order to present pertinent facts which may be of assistance in
arriving at a decision as to whether or not a special effort will be
initiated at this time to achieve a thermonuclear weapon or to determine
conclusively its lack of feasibility.
2. Hypothesis: Sole Possession by the USSR. From
both a practical and a psychological point of view it is considered that
the thermonuclear weapon is to the fission weapon as the fission weapon
is to a conventional bomb. In terms of energy release the pertinent
ratio is about 2000–40000:1. [2000–4000:1?] In
terms of comparative area of blast damage the ratio is about 30:1. Aside
from the psychological potential
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which automatically exists through enemy exploitation of this ratio
differential, there is the added factor that if we fail to develop a
thermonuclear weapon and thereby lack knowledge of its positive effects,
we shall be unable to counter possible enemy exploitation of the
frightening and paralyzing fiction which has become associated from time
to time with thermonuclear explosions. Accordingly it must be
anticipated that the development of a thermonuclear weapon by the USSR
in advance of the United States, particularly if the announcement
follows secret development, would have a profoundly demoralizing effect
on the American people. It would have grave psychological and political
repercussions which might raise serious question concerning the
continued unity of spirit, confidence and determination among the
nations of the Western world. The situation today is strikingly parallel
to that of a few years ago when this nation was engaged in a desperate
race to develop a fission bomb before Germany. From the Soviet point of
view sole possession of the thermonuclear weapon would place in their
hands an offensive weapon of the greatest known power possibilities. It
would provide the Soviet leaders, people and satellites with a
tremendous psychological boost which in peacetime could lead to
increased truculence in international affairs and increased political
infiltration in nations of the western world. The tremendous “blackmail”
potential of the thermonuclear weapon would serve the USSR well in its
aims to impose its will upon the nations of Europe and to alienate these
nations from the Western camp. In time of war sole possession of the
thermonuclear weapon coupled with tremendous superiority of conventional
military forces would provide the Soviets with the necessary balance to
current Western unity and to our superior fission weapons stockpile to
enable them to risk hostilities for the rapid achievement of their
objectives. The above developments cannot be forecast with certainty;
however, the materialization of one or more of these possible
developments would have such a grave effect upon our world position as
to force a complete re-evaluation of our strategic plans and of our
national objectives in peace and in war. The inevitable jeopardy to our
position as a world power and to our democratic way of life would be
intolerable.
3. Hypothesis: Sole Possession by the US. The sole
possession of this weapon by the US would cause all of the practical and
many of the psychological advantages of possession of thermonuclear
weapons to accrue to our side, and may act as a possible deterrent to
war. From the practical point of view possession of this weapon would
add materially to the striking power of our forces against those
important tactical and strategic objectives which are particularly
adapted to a thermonuclear weapon. For example, large concentrations of
enemy troops
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and matériel such
as occur frequently in war (the Normandy invasion, the defense of
Stalingrad, the Bulge break-through, large dumps, singularly important
airplane concentrations, and other such large but lucrative targets)
which would now require multiple delivery of fission weapons, could be
destroyed or critically disrupted with a single thermonuclear weapon.
Since this destruction could be applied throughout the target area with
simultaneity, the value of surprise could be exploited to the maximum.
Effective destruction of the above target types may well lead to
decisive results since such concentrations normally occur in connection
with critical operations in war. Moreover, attack of enemy atomic air
bases with a thermonuclear weapon may be the only effective defense from
enemy atomic attack. If, on the other hand, enemy knowledge of our
possession of this weapon causes them so to conduct operations as to
avoid concentrations of troops and materiel to a materially greater
extent than is now indicated by our possession of fission weapons, we
shall have forced them to abandon the source of their greatest strength,
employment of mass. There are additional advantages of the thermonuclear
weapon which are not provided by a proportionally greater number of
fission weapons. The thermonuclear weapon promises in the high ranges of
energy release to be more efficient in the utilization of available, ore
and production capacity per unit of damage area. Further, for those
military uses particularly adapted to the thermonuclear weapon,
employment of this weapon will reduce the delivery problem of the
required destructive effect through increased ease of maintaining the
smaller force in higher state of attack readiness and through reduced
cost of maintenance and protection of this force. These factors will
increase in significance in the next few years. It is currently clear
that in the normal fluctuations of effectiveness as between defensive
weapons and offensive weapons, it is becoming increasingly difficult to
maintain a predetermined amount of attack potential by long-range
aircraft without increase in force requirements. The development of the
thermonuclear weapon would tend to arrest this trend by allowing the
packaging of some of our retaliatory attack in a small number of
units.
The development of a vehicle to carry the thermonuclear weapon to its
target is a problem which remains to be solved in conjunction with the
development of the weapon itself. The trend of this vehicular
development will depend largely upon the anticipated characteristics and
physical dimensions and weight of the weapon. It is impracticable at
this time to anticipate the exact nature of the eventual carrier. It is
apparent that, for the US, a large airplane will be a basic requirement
initially. The following possibilities suggest themselves: a drone
aircraft; an aircraft with a detachable parasite escape ship, the bomb
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to be exploded by a time
mechanism; an improved B–36 type with an underbelly weapon attachment;
etc. In consideration of the technical problems to be solved in the
development of the weapon as compared to the carrier, it is believed
that the carrier problem, although difficult, is the lesser of the
two.
4. Hypothesis: Possession by Both Countries. It is
clear that under these conditions the world would be precipitated into
the atomic age much more rapidly than would otherwise be the case. Such
requirements as dispersal of industry, dispersal on the battlefield,
avoidance of reliance upon ports, beachheads, large airfields, etc.,
would become more mandatory and on a considerably larger scale than is
now indicated by mutual possession of fission weapons. Under such
conditions it can be anticipated that great stress will be placed by
each protaganist on the attempt to deliver as the initial act of
hostilities a paralyzing blow on the offensive atomic capabilities of
the enemy such as air bases for the atomic carrier force. Accordingly it
appears reasonable to forecast that great effort must be made in the
fields of research and development and the development of suitable
techniques of operational employment which will allow the required
dispersion in order to achieve an adequate degree of invulnerability of
the retaliatory attack force.2
5. Hypothesis: Firm Determination of
Infeasibility. Because of the tremendous military implications
which would result from the development of a thermonuclear weapon, it is
imperative to determine conclusively the feasibility of a thermonuclear
explosion and its characteristics. Such determination is essential for
US defense planning, preparations for retaliation, and direction for our
research and development programs. There are undoubtedly a number of
possible social, psychological and moral objections which may be
considered to argue against research and development by the United
States leading to the development and test of a thermonuclear weapon.
The above considerations decisively outweigh such objections. The United
States has enjoyed and relied upon a measure of technological advantage
over the USSR. This advantage lies principally in our industrial
capacity, our stockpile of atomic weapons, and our ability to deliver
these weapons. We no longer have a monopoly of atomic weapons, which
fact lessens our degree of technological advantage. There are
indications that the USSR also has some capability of producing a
thermonuclear weapon. To stop arbitrarily our atomic research at the
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frontier of thermonuclear
reactions would guarantee the loss of our technological advantage and
further would not prevent development of this weapon by the USSR as long
as war remains a possibility. If we do not determine the feasibility of
a thermonuclear weapon before a war, we would be forced to make this
determination on a “crash” basis upon the initiation of hostilities. In
the meantime our military planners would be faced with a dilemma in
military operations. To plan needlessly on the basis of enemy possession
of this weapon would result in granting the enemy the historical
advantages which accrue to a protagonist when his strength is
over-estimated. We would be forced to abandon effective techniques of
warfare on the erroneous basis that such techniques were no longer
sound. The ultimate detrimental effect upon our strategic and diplomatic
intentions with regard to western Europe can hardly be estimated. On the
other hand, the acceptance of a risk by undertaking operations on the
assumption that the enemy does not possess this weapon could lead to
disastrous results. In view of the above it is considered that the cost
involved in a determination of feasibility of a thermonuclear explosion
is insignificant when compared with the urgency to determine firmly the
ceiling on atomic development.
6. Consideration of Current Policy on International
Control. The military is in strong support of the United States
position in the United Nations on international control of atomic
energy. Preliminary studies indicate that the possible existence of a
thermonuclear weapon does not appear to warrant change of the attitude
of the military, with the exception that serious consideration must be
given to the probability that adequate control would be more difficult
and that successful violation of control would be much more significant.
Detailed studies by the United States in this regard are indicated and
should be undertaken without delay.
7. Considerations of Timing and Intensity of
Effort. The overriding considerations which indicate a
necessity for the development and test of a thermonuclear weapon occur
in conjunction with the analysis of the situation which would exist if
the USSR had sole possession of a thermonuclear weapon. Accordingly our
plans must be on such a scale that we not lose an appreciable amount of
time in determining the feasibility of a thermonuclear weapon. The
following program is considered to constitute the minimum effort which
should be undertaken in this field at this time:
-
a.
- The determination of the technical feasibility of a
thermonuclear explosion.
-
b.
- The necessary ordnance developments and carrier programs
should proceed concurrently with a above
and should not necessarily await trial of a test thermonuclear
assembly.
-
c.
- Sufficient reactors should be constructed or modified to
provide the necessary amount of tritium for the test in a above.
-
d.
- Decisions pertaining to the production of thermonuclear
weapons in any quantity should be deferred pending further
determination of the ultimate feasibility of a thermonuclear
explosion and the feasibility of an appropriate weapon
carrier.
8. Considerations Regarding Security. There are
many facets to the question of whether it should be made a matter of
public knowledge that the United States is engaged in an active effort
to develop a thermonuclear weapon. It is considered that public
discussion once initiated and encouraged is extremely difficult to
control and inevitably leads to a greater disclosure than originally
intended. An additional factor of military significance is the
divergence of opinion among scientific circles in this country relative
to the feasibility of a thermonuclear explosion. It can be expected that
such divergence of opinion exists in the USSR on at least an equivalent
parity. If the United States announces that we are engaged in an active
effort to develop a thermonuclear weapon, such positive knowledge would
give added credence and ascendency to the Soviet group sponsoring
development in this field and may result in an earlier start or greater
impetus to the Soviet program. For the above two reasons, it is
considered that any decisions or actions pertaining to a United States
effort to develop a thermonuclear weapon or any determination of its
feasibility is military information of the highest security
classification.
