The Einstein-Szilard letter that warned The USA of Nazi Atomic Weaponry

The Nazi’s had the potential to develop nuclear arms.

Einstein predicted that the Nazi’s had the potential to produce atomic weaponry. In a letter from Szilard and signed by Einstein the two warn Roosevelt of a rising threat.

The letter urges the United States to establish their own nuclear program, beating Germany to the punch.

Letter to U.S. President Franklin D. Roosevelt by Albert Einstein
By Albert Einstein, Public Domain, Link

The Albert-Szilard letter was the catalyst for the establishment of the Manhattan Project and eventual development of the atomic bomb. Had the letter not been sent the outcome of World War Two may have been completely different.

The history altering letter warned that:

“In the course of the last four months it has been made probable — through the work of Joliot in France as well as Fermi and Szilárd in America — that it may become possible to set up a nuclear chain reaction in a large mass of uranium, by which vast amounts of power and large quantities of new radium-like elements would be generated. Now it appears almost certain that this could be achieved in the immediate future....Einstein and Szilard

Image: Einstein and Szilard, Source: Atomic Heritage

This new phenomenon would also lead to the construction of bombs, and it is conceivable — though much less certain — that extremely powerful bombs of a new type may thus be constructed. A single bomb of this type, carried by boat and exploded in a port, might very well destroy the whole port together with some of the surrounding territory. However, such bombs might very well prove to be too heavy for transportation by air.."

Specifically warning the US of Germany’s ability to produce atomic weapons:

"I understand that Germany has actually stopped the sale of uranium from the Czechoslovakian mines which she has taken over. That she should have taken such early action might perhaps be understood on the ground that the son of the German Under-Secretary of State, von Weizsäcker, is attached to the Kaiser-Wilhelm-Institut in Berlin where some of the American work on uranium is now being repeated..."

Roosevelt replied to the letter and decided to take immediate action.


Roosevelt's answer to Einstein's letterISBN 3-03823-182-7., Public Domain, Link

Einstein did not work on the Manhattan Project, as a strong pacifist The American Army denied him the right to work, saying his pacifist views made him a security risk.

Einstein later regretted signing the letter, as it led to the creation of the atomic bomb:

Had I known that the Germans would not succeed in developing an atomic bomb, I would have done nothing.

Header: Simple Wikipedia, The atomic bomb mushroom cloud over Nagasaki on August 9, 1945

Tune into GENIUS on the 24th of April 8.30pm on National Geographic

Related Articles

Discuss this article


Never miss a Nat Geo moment

Your email address
We use our own and third-party cookies to improve our services, personalise your advertising and remember your preferences. If you continue browsing, or click on the accept button on this banner, we understand that you accept the use of cookies on our website. For more information visit our Cookies Policy AcceptClose cookie policy overlay