powerful detonation, and that effective means exist to guard against
the blast and radiation produced.


1.1 HISTORICAL BACKGROUND OF PROJECT TRINITY

The development of a nuclear weapon was a low priority for the United
States before the outbreak of World War II. However, scientists
exiled from Germany had expressed concern that the Germans were
developing a nuclear weapon. Confirming these fears, in 1939 the
Germans stopped all sales of uranium ore from the mines of occupied
Czechoslovakia. In a letter sponsored by group of concerned
scientists, Albert Einstein informed President Roosevelt that German
experiments had shown that an induced nuclear chain reaction was
possible and could be used to construct extremely powerful bombs (7;
12)*.

* All sources cited in the text are listed alphabetically in the
reference list at the end of this volume. The number given in the
text corresponds to the number of the source document in the reference
list.

In response to the potential threat of a German nuclear weapon, the
United States sought a source of uranium to use in determining the
feasibility of a nuclear chain reaction. After Germany occupied
Belgium in May 1940, the Belgians turned over uranium ore from their
holdings in the Belgian Congo to the United States. Then, in March
1941, the element plutonium was isolated, and the plutonium-239
isotope was found to fission as readily as the scarce uranium isotope,
uranium-235. The plutonium, produced in a uranium-fueled nuclear