The Secret Sentry is an extraordinary book, providing much more information about the activities of the National Security Agency (NSA) then was previously available. Some people will know that the NSA history unit has recently released volumes of material on aspects of the history of the agency. In some measure these releases were due to Matthew Aid, the author of the book. Matthew served in the old Air Force Security Service, one of the service arms of NSA. He has experience inside the system but has done extraordinary research in the records held by the National Archives and Records Administration facility at College Park. The quality of his efforts have been so good that other people, once they became aware of his endeavors, who worked in the NSA world have shared experiences with him. Matthew discovered that the people who were supposed to cull records before they were transfered to College Park missed a lot of documents. He also learned to effectively use the Freedom of Information Act to nudge documents out of NSA and other intelligence organizations. The net result is a work that provides more insight into the operations of the Signal Intelligence (SIGINT) community than has been available before. It is an up and down story with both successes and failures. But the important insight that emerges is that SIGINT often has provided the greatest volume of material used by the services, other intelligence agencies, and the White House. During the Vietnam War much of the intelligence that the military and political structure used to fight the conflict came from SIGINT. Also, there were times when NSA broke into Russian communications, although not often enough. Matthew provides an surprising amount of information on the use and misuse of SIGINT from the Gulf War to the present. His history also makes clear, that as was the case with Pearl Harbor, SIGINT information can be so volumonous that important facts can lost or overlooked until it is too late. He also reminds us that when polititians become their own intelligence officers the result is often dismal, if not to say distorted.
For the sake of ethical accountability, I wish to disclose that I know Matthew Aid and have been after him for years to publish his research. I also was a member of the NSA family, having served in the old Army Security Agency, with two tours of Vietnam (his depiction of SIGINT use in Vietnam is the best I have seen). It should also be understood that many of the chapters in the book could individually be expanded into book-length studies. Matthew has much more data than he was able to use in the book. Actually, the publisher, Bloomsbury, is to be acknowledge to allow almost a quarter of the book to be footnotes. It is unusual for a book on intelligence, particularly one from a commercial publisher, to be so heavily documented. A final note: the book is quite accessible and a fast read because of the way it is organized. The book could have used a bigger acronym list,perhaps a brief explaination of the SIGINT cycle as well as how the individual service SIGINT organizations functioned in the NSA system. But, no matter, you come away from this book knowing a lot more than you ever did before.