THE WHITE HOUSE
August 6, 1945
STATEMENT BY THE PRESIDENT OF THE UNITED STATES
Sixteen hours ago an American airplane dropped one bomb on Hiroshima, an
important Japanese Army base. That bomb had more power than 20,000 tons of
T.N.T. It had more than two thousand times the blast power of the British
"Grand Slam" which is the largest bomb ever yet used in the history of
The Japanese began the war from the air at Pearl Harbor. They have been
repaid many fold. And the end is not yet. With this bomb we have now
added a new and revolutionary increase in destruction to supplement the
growing power of our armed forces. In their present form these bombs are
now in production and even more powerful forms are in development.
It is an atomic bomb. It is a harnessing of the basic power of the
universe. The force from which the sun draws its power has been loosed
against those who brought war to the Far East.
Before 1939, it was the accepted belief of scientists that it was
theoretically possible to release atomic energy. But no one knew any
practical method of doing it. By 1942, however, we knew that the Germans
were working feverishly to find a way to add atomic energy to the other
engines of war with which they hoped to enslave the world. But they
failed. We may be grateful to Providence that the Germans got the V-1's
and the V-2's late and in limited quantities and even more grateful that
they did not get the atomic bomb at all.
The battle of the laboratories held fateful risks for us as well as the
battles of the air, land, and sea, and we have now won the battle of the
laboratories as we have won the other battles.
Beginning in 1940, before Pearl Harbor, scientific knowledge useful in war
was pooled between the United States and Great Britain, and many priceless
helps to our victories have come from that arrangement. Under that general
policy the research on the atomic bomb was begun. With American and
British scientists working together we entered the race of discovery
against the Germans.
The United States had available the large number of scientists of
distinction in the many needed areas of knowledge. It had the tremendous
industrial and financial resources necessary for the project and they could
be devoted to it without undue impairment of other vital war work. In the
United States the laboratory work and the production plants, on which a
substantial start had already been made, would be out of reach of enemy
bombing, while at that time Britain was exposed to constant air attack and
was still threatened with the possibility of invasion. For these reasons
Prime Minister Churchill and President Roosevelt agreed that it was wise to
carry on the project here. We now have two great plants and many lesser
works devoted to the production of atomic power. Employment during peak
construction numbered 125,000 and over 65,000 individuals are even now
engaged in operating the plants. Many have worked there for two and a half
years. Few know what they have been producing. They see great quantities
of material going in and they see nothing coming out of those plants, for
the physical size of the explosive charge is exceedingly small. We have
spent two billion dollars on the greatest scientific gamble in history--
But the greatest marvel is not the size of the enterprise, its secrecy, nor
its cost, but the achievement of scientific brains in putting together
infinitely complex pieces of knowledge held by many men in different fields
of science into a workable plan. And hardly less marvelous has been the
capacity of industry to design, and of labor to operate, the machines and
methods to do things never done before so that the brain child of many
minds came forth in physical shape and performed as it was supposed to do.
Both science and industry worked under the direction of the United States
Army, which achieved a unique success in managing so diverse a problem in
the advancement of knowledge in an amazingly short time. It is doubtful if
such another combination could be got together in the world. What has been
done is the greatest achievement of organized science in history. It was
done under high pressure and without failure.
We are now prepared to obliterate more rapidly and completely every
productive enterprise the Japanese have above ground in any city. We shall
destroy their docks, their factories, and their communications. Let there
be no mistake; we shall completely destroy Japan’s power to make war.
It was to spare the Japanese people from utter destruction that the
ultimatum of July 26 was issued at Potsdam. Their leaders promptly
rejected that ultimatum. If they do not now accept our terms they may
expect a rain of ruin from the air, the like of which has never been seen
on this earth. Behind this air attack will follow sea and land forces in
such numbers and power as they have not yet seen and with the fighting
skill of which they are already well aware.
The Secretary of War, who has kept in personal touch with all phases of the
project, will immediately make public a statement giving further details.
His statement will give facts concerning the sites at Oak Ridge near
Knoxville, Tennessee, and at Richland near Pasco, Washington, and an
installation near Santa Fe, New Mexico. Although the workers at the sites
have been making materials to be used in producing the greatest destructive
force in history they have not themselves been in danger beyond that of
many other occupations, for the utmost care has been taken of their safety.
The fact that we can release atomic energy ushers in a new era in man's
understanding of nature's forces. Atomic energy may in the future
supplement the power that now comes from coal, oil, and falling water, but
at present it cannot be produced on a basis to compete with them
commercially. Before that comes there must be a long period of intensive
It has never been the habit of the scientists of this country or the policy
of this Government to withhold from the world scientific knowledge.
Normally, therefore, everything about the work with atomic energy would be
But under present circumstances it is not intended to divulge the technical
processes of production or all the military applications, pending further
examination of possible methods of protecting us and the rest of the world
from the danger of sudden destruction.
I shall recommend that the Congress of the United States consider promptly
the establishment of an appropriate commission to control the production
and use of atomic power within the United States. I shall give further
consideration and make further recommendations to the Congress as to how
atomic power can become a powerful and forceful influence towards the
maintenance of world peace.