Truman Library, Truman Papers, PSF–Subject File

Memorandum by the Chief of Special Projects, Joint Congressional Committee on Atomic Energy (Mansfield), to the Chairman of the Committee (McMahon)1

secret

Subject: Some Comments on Tactical Atomic Weapons

The following comments are in response to your request.

Tactical atomic weapons hold forth the promise of a revolution in land war which can be compared to the revolution in air war brought about by the Hiroshima and Nagasaki bombs. General Collins tells us that the prospect of these weapons puts the defense of Western Europe in a completely new—and far more favorable—light. From General Bradley, we hear that the development of such weapons may spell the end of mass concentrations of troops.

Atomic weapons used tactically are the natural armaments of numerically inferior but technologically superior nations. They are the natural answer to the armed hordes of the Soviet Union and its satellites. Their coming into being should immeasurably strengthen Western Europe’s will-to-resist, since they will decisively help to shift the [Page 159] balance of military power toward the free world and against the slave world.

One might therefore suppose that we would now be orienting our entire defense program around the rapid development and bringing into being of tactical atomic weapons. In truth, however, we have been curiously tardy and fainthearted in getting this program started. My inquiries lead me to believe that only a very minor fraction of our total research and development program is now directed toward achieving tactical A-weapons as quickly and in as large quantity as possible.

There is a compelling analogy between our present effort in this field and our effort to amass a stockpile of strategic weapons in the days immediately following Hiroshima. Six years ago, it was generally recognized that weapons of mass destruction had fundamentally changed the anatomy of air power. Indeed, this conviction found substance in our official defense thinking—we proceeded to place overwhelming reliance on the deterrent power of our atomic stockpile. And yet—despite this one-weapon-in-our-arsenal situation—we allocated less than one-fortieth of our total military spending to the manufacture of these weapons. Our deeds were strangely out of line with our words.

Just as, six years ago, we suffered from strategic myopia—failing to devote enough resources to the trump card of the free world—so now we appear to be suffering tactical myopia—failing to devote enough skill and energy to developing these revolutionary new weapons. Of course, we hear great promises of things to come in the tactical field—just as we heard much about the fearful destructive potentialities of our strategic stockpile, at a time when there were two bombs in our locker. But the momentous and historic implications of tactical atomic weapons have not yet truly permeated the thinking of the military—nor does there now exist an all-out program to translate promises of future developments into the hard stuff of fissionable materials.

The case should not be overstated. All three services are working on the thorny problems that stand between us and a family of tactical weapons existing in quantities large enough to hold the Red armies at bay. In addition, the military has farmed out important tactical studies to contractors, e.g., to California Tech, to the Rand Corporation at Santa Monica, and to the Army’s Operations Research Office at Johns Hopkins.

But what needs stressing is the elementary nature of the research projects now under way. These undertakings are, without exception, exploratory inquiries—they aim more at defining the problem rather than at offering specific plans for action. For instance, Dr. Robert Batcher, the former AEC Commissioner now participating in the “Vista Project” at Cal Tech, told me that when his group’s work is finished—presumably at the end of this year—they will probably [Page 160] come forward with no more than a series of recommendations for further studies.

If our present rate of progress is unchanged, it will very probably be mid-1953 before we have an agreed-upon body of doctrine concerning the deployment and use of tactical A-weapons.

This brings out one of the peculiarities of this problem area—the actual development of tactical atomic weapons themselves has been more rapid than the development of our thinking on how to use them. We have emerging an entire family of atomic weapons designed for tactical use; we do not now have intra- or even inter-service agreement on how these weapons will be used and which ones are the prospective best military bets.

In our thinking about these weapons, there are two broad problems to be solved—and these might be described as the “hardware problem” and the “allocation problem.”

The hardware problem consists of four inter-related questions: (1) What should be the make-up of our ultimate family of atomic weapons? (2) How can they be most effectively delivered to their targets? (3) Against what types of targets should these weapons be employed? and (4) Which services should be empowered to carry out what tactical atomic assignments, and what new command problems will be created by the coming of these weapons?

In turn, these four questions present a host of smaller issues: What is the comparative effectiveness of atomic artillery pieces versus airdrops? Are large-diameter, large-yield weapons—which can be carried only in relatively large planes—better than small-diameter, small-yield weapons—which have less destructive power but greater ease of deliverability? Does the atomic howitzer represent a sensible military requirement, or does it basically reflect the Army’s desire to get into the atomic act? Can these new weapons be used efficiently against personnel, or should they be primarily employed against structures and materiel? Will they be used to better advantage in close support of ground troops, or will interdiction—the destruction of bridges, etc.—constitute their main application? And what about the problem of air-ground liaison? Does the danger of hitting our own troops tip the balance in favor of the marine type of tactical air command?

Two things are apparent concerning all these hardware questions. First, these problems cannot be solved quickly and easily—for purely technical reasons it will inevitably take a long time to thrash them out. Second, these questions are—insofar as the military is concerned—politically explosive. The relative stature of each of the three services will intimately depend on how they are answered—they hold out the possibility of creating new versions of the B-36–super carrier controversy.

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There is little doubt that with greater effort, the hardware studies can be measurably hastened. The Joint Committee may indeed find it desirable to press for a more ambitious research program—perhaps the timetable can be stepped up by six months. Yet, by their very nature, these research problems will be protracted.

The result is that the tactical picture—if regarded in terms of exactly what weapons we will need and exactly how we want to use them—will really not be clear until 1953 at the earliest.

Now, what of the allocation problem? No doubt the question of intra-service allocation of tactical atomic weapons will be a great coming bone of contention. We will see, and indeed are already seeing, a renewal of the old arguments about the “balanced force” against the primacy of one branch of the service.

But in describing the allocation problem, I am not at this moment thinking of intra-service rivalry; I have in mind instead the following two questions: (1) How does the prospect of tactical weapons bear upon the total amount of our national resources that should be allocated to the atomic program? (2) How should our stockpile of fissionable materials be allocated for strategic or tactical use?

If—as I have seen suggested—atomic energy used tactically may be 300 times more economical than conventional high explosives—it seems to follow that our program should be expanded far beyond the dimensions now envisaged by even the most ambitious planners in the Executive Branch. An educated guess suggests that tactical A-weapons—even if made of $40-per-pound raw materials in contrast to the $8 price now prevailing—will still be by far the cheapest military buy. Another educated guess suggests that there will be almost immeasurable tactical uses—uses that must somehow be reconciled with the now almost limitless capacity of the Strategic Air Command to absorb profitably all the fissionable material we can turn out.

So here is one constant in our calculations—we shall want tactical weapons in what can now be termed astronomical quantities. Very probably we will want them numbered in the tens of thousands. And here is the second constant—for an indefinite period of time, the demands of strategic bombing can use all the fissionable material now scheduled for production. Even given the dimensions of the present expansion program, we will have to rob Peter to pay Paul if we are fully to exploit tactical uses. We cannot do this and, at the same time, neutralize Russian industry. If this is the case, we must again raise our sights in considering the scale and scope of our atomic project—we must certainly raise them well beyond the dimensions of the present expansion program.

By 1953, this unbounded need for tactical weapons will be quite apparent. But requirements set in 1953 will not assert themselves in fissionable materials until 1957 or 1958.

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Our problem, therefore, is to telescope time and lay down requirements for fissionable materials now that will be very evident in 1953. I believe this can be done. Irrespective of the shape of the family of atomic weapons that will come into being two or three years hence, it is possible today to define the general magnitude of the role that tactical A-weapons will play in our defensive strategy. Five years hence, that is, will we want these weapons in scores, hundreds, thousands, or tens of thousands? Up to what point will these weapons represent a good military buy? In—say—1956, will it make sense to spend perhaps $200 million a year for tactical uses or would it be economical to spend ten times or even twenty or thirty times that amount?

Notwithstanding our present rudimentary knowledge concerning the hardware questions, we can now make very good predictions about the future minimum dimensions of our tactical program. Normally, of course, the military does not lay down large-scale requirements for a weapon until it has been field-tested. In the case of conventional armaments, this reluctance to buy a pig in a poke is sensible—there is no point, for instance, to committing oneself to a particular artillery piece until it has been tested under field conditions.

But—insofar as the setting of requirements is concerned—atomic weapons must be sharply distinguished from conventional armaments. Once there is some agreement on more or less appropriate ratios between the output of plutonium and uranium-235, we can go ahead and produce, without paying too much heed to what particular shape the fissionable material ultimately assumes. This material can be stored indefinitely; it can be prefabricated into new cores with relative ease.

This means that in the atomic field, it makes decided sense to set requirements for fissionable materials in advance of detailed requirements for a specific kind of weapon.

So, in deciding the allocation question—the question of how much atomic material we should turn out, and the question of how we shall earmark it for tactical or strategic use—we can make our basic policy decisions now and save precious time.

Regarded in its fundamentals, the allocation problem is uniquely political rather than military, and it must be squarely met by our civilian leaders. Grand strategy is at stake here and strategy should determine tactics rather than vice versa. Will we use the bulk of our fissionable material to pulverize Soviet industry at the possible cost of Russian occupation of Western Europe? Will we use the major portion of our atomic stuffs to help hold the Red army at the Elbe at the cost of neglecting vital Soviet production centers? Or will we have a program bold enough to accomplish both the defeat of the Red armies and the neutralization of Soviet industry? Only properly constituted civilian authority, properly advised by the military, can venture answers to these basic questions.

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For its own part, the Joint Committee may find it desirable to push forward on the following fronts: (1) Urge upon the military a more ambitious research program—one truly in keeping with the epochal importance of tactical atomic weapons. (2) Try to secure from the military—at the earliest possible date—estimates of expected requirements for these weapons expressed in terms of general order of magnitude. And by “requirements”, I of course mean estimates based upon actual military need rather than upon supposed availability of raw materials. It is high time that all of us recognize that—within very broad limits—we can have all the raw material we want, provided we are willing to pay the price.

Yet ultimately, of course, only the President and the Congress can speak authoritatively and constitutionally upon the momentous questions posed by the coming advent of tactical atomic weapons. It is their high and solemn responsibility to grapple with the issues of grand strategy, and to decide how the vast force of the split atom can best promote the defense of the free world. We are now on the threshold of a revolution in the art of warfare; the President and the Congress have it within their power to strike a decisive blow for the cause of freedom.

J. K[enneth] M[ansfield]
  1. The source text bears the following handwritten notation by President Truman: “Atomic file. HST.”