Intelnote - The Pearl Harbor History Associates are happy to be able to bring this work to the Internet after decades of being hidden in the stacks or costing $100+ for each volume on the used market. We hope this will be useful in the study of the events leading up to the attack on Pearl Harbor and the study of events leading to wars whenever they occur. Our greatest wish is that by learning more about how wars start we can learn more about how to prevent them, and some day will come the time when we will "study war no more."

Foreword
The Department of Defense is releasing for public use and research this multi-volume study giving the "MAGIC" or communications intelligence background of the 1941 Pearl Harbor disaster. In its review of classified records pursuant to E.O. 11652, the Department of Defense decided that it was in the public interest to declassify the intelligence which the U.S. obtained from the communications of its World War II enemies. This study contains a major part of the communications intelligence which the U.S. derived from intercepted Japanese communications during 1941.


The Magic Background To Pearl Harbor

The documentation presented here is both voluminous and significant. The large volume of intelligence concerning Japanese secret plans, policies, and activities which U.S. cryptologic specialists produced will augment the information already available on Pearl Harbor from Congressional and other public hearings. Of particular importance in this study is the correlation of the intelligence with the discussions of Secretary of State Hull and Japanese Ambassador Nomura in the critical months before Pearl Harbor. Scholars no doubt will find new challenges in this voluminous intelligence information as they examine not only the decisions made by the U.S. but also the intelligence which influenced and occasionally prompted those decisions.

The Magic Background To Pearl Harbor