Much research has been devoted to the effects of nuclear weapons. But
studies have been concerned for the most part with those immediate
consequences which would be suffered by a country that was the direct
target of nuclear attack. Relatively few studies have examined the
worldwide, long term effects.

Realistic and responsible arms control policy calls for our knowing more
about these wider effects and for making this knowledge available to the
public. To learn more about them, the Arms Control and Disarmament Agency
(ACDA) has initiated a number of projects, including a National Academy of
Sciences study, requested in April 1974. The Academy's study, Long-Term
Worldwide Effects of Multiple Nuclear Weapons Detonations, a highly
technical document of more than 200 pages, is now available. The present
brief publication seeks to include its essential findings, along with the
results of related studies of this Agency, and to provide as well the basic
background facts necessary for informed perspectives on the issue.

New discoveries have been made, yet much uncertainty inevitably persists.
Our knowledge of nuclear warfare rests largely on theory and hypothesis,
fortunately untested by the usual processes of trial and error; the
paramount goal of statesmanship is that we should never learn from the
experience of nuclear war.

The uncertainties that remain are of such magnitude that of themselves they
must serve as a further deterrent to the use of nuclear weapons. At the
same time, knowledge, even fragmentary knowledge, of the broader effects of
nuclear weapons underlines the extreme difficulty that strategic planners
of any nation would face in attempting to predict the results of a nuclear
war. Uncertainty is one of the major conclusions in our studies, as the