"Fuer und Wider Hitlers Bombe", i.e. "The pros and cons on >>Hitler's bomb<<", is a successor to Rainer Karlsch's "Hitlers Bombe", which in 2005 kindled a hitherto smouldering debate on the dimensions of Nazi Germany's WW2 nuclear weapons program.

"Hitler's Bombe" culminated in the assumption that small-scale nuclear devices were tested under the auspices of the SS in October 1944 and in March 1945. Many physicists around the world would disagree, since the Germans were short of enriched uranium and obviously did not operate any nuclear reactors to breed plutonium-239. In 2006 PTB, the German National Bureau of Standards, was unable to find conclusive evidence of a nuclear excursion in soil samples taken from the Ohrdruf (Thuringia) military training area - one of the alleged test sites.

Now the dispute is revived. In a dozen articles and backed by historians, journalists, engineers, physicists, geophysicists and even designers of Soviet nuclear weapons, editors Rainer Karlsch and Heiko Petermann have addressed a few unresolved or mistaken issues.

"Fuer und Wider Hitlers Bombe" consists of two parts - the first one more physically, the second one more historically oriented. Several contributions deal with various aspects of the Ohrdruf explosion. The approximate yield of that event is estimated. Rarely known Polish post-war attempts to reduce the critical mass, probably based on German knowledge, are mentioned - an issue of utmost importance for today's nuclear nonproliferation activities. A comparison of aerial photographs both from the Trinity site and the Ohrdruf military training area reveals why it is so difficult to detect any visible traces of the German near-surface explosion 60 years later on. Seismograms of near-by observatories, which may have registered the Ohrdruf event, were "borrowed" by the Soviets in the Sixties and never reappeared. In a U.S. interrogation report dating one day (!) after the Trinity test a witness of a German test explosion gave a more precise description of the bomb's effects than William Laurence, the famous reporter, who accompanied the Nagasaki air raid and was allowed to publish his notes in the New York Times on September 9, 1945.

In the second part the beginnings of German fusion research are reviewed. The role of Erich Schumann, then Army coordinator of nuclear weapons research, is evaluated. Another article investigates the possibility of a nuclear attack of the American east coast with the futuristic German "Saenger" bomber. Was German actinides research really constricted by Otto Hahn after Kurt Starke's independent discovery of element 93 (neptunium)? Some protagonists continued their weapons-related work in the post-war Federal Republic of Germany, as several patent applications of "mini-nukes" reveal.

The most compelling result of this book is that Karlsch's proposal of a crude implosive test device utilising the coupling of fission and fusion processes is judged to have been in reach for German physicists like Walter Gerlach and Kurt Diebner. Always lacking the fissile material for pure fission bombs Gerlach concluded in May 1944 that "the release of nuclear energy is to be performed not only by fission but by alternative means." Vladimir Mineev and Alexander Funtikov, designers of nuclear weapons in the former Soviet Union, suggest the Germans might have been fully aware of the "boosting" principle. If a small quantity of thermonuclear fuel - a 1:1 mixture of deuterium and tritium gas or lithium hydrides - is placed appropriately into the pit of the device, the fissile material is much more efficiently consumed by high-energy fusion neutrons; that is, a much higher fission yield from a given quantity of U-235 or Pu-239 may be obtained. The fusion process itself adds negligibly to the total yield. It is important in this context that boosting reduces the critical mass substantially. Conventional wisdom tells us the boosting principle was first mentioned for military purposes in November 1945, when it was included in a patent application filed at Los Alamos.

After reading "Fuer und Wider Hitlers Bombe" it becomes quite obvious that outside of Heisenberg's "Uranium Club" several groups were willing to give Hitler the ultimate vengeance weapon. From mid-1944 onwards both the Army and Navy, the Reich's Postal Office and last but not least the SS worked feverishly on the construction of a nuclear weapon.

So did Hitler really own a nuclear weapon in the waning days of WW2? As expected, "Fuer und Wider Hitlers Bombe" does not show any blueprints of the mysterious German devices. And again it does not offer any first-hand proof of nuclear weapons tests in wartime Germany.

But this book leaves more pros than cons. Karlsch and Petermann have made a great point in intensifying an urgently needed discussion on these issues. If they are right they have changed a historical paradigm.

Is it a must-read? Of course "Fuer und Wider Hitlers Bombe" will not be all things to all readers. The community of professional nuclear weapon scientists will likely find parts of the book simplistic, but should also find parts that offer significant insight. A lot of nonspecialists and interested laymen, too, may appreciate and greatly enjoy this opportunity to delve more deeply into the history of the atomic era.

"Fuer und Wider Hitlers Bombe" contains a few annoying misprints and insignificant errors. The meaning of some figures is unclear (e.g., of some U.S. nuclear weapons tests). On the whole, technical and historical contributions are balanced quite well.

To promote the discussion on a more international level it would be advantageous if an English edition of both "Hitlers Bombe" and "Fuer und Wider Hitlers Bombe" was at hand soon.

Strangely enough, corroborating evidence of an SS-dominated nuclear weapons program comes from the Near East: In his memoir (Damascus 1999, p. 127, p. 162ff) Muhammad Amin Al-Husayni, the former Grand Mufti of Jerusalem, a fanatic anti-semite and multiple visitor to Nazi Germany, focusses on a meeting with Himmler in July 1943. Himmler would have passed confidential information on to him - "known to only ten persons in the whole Reich ... Germany about to build an atomic weapon." The Reichsfuehrer further told Al-Husayni Great Britain and the U.S. were striving hard to catch up with their own nuclear weapons programs, "but we are still ahead. We will possess atomic weapons three years earlier than our
enemies. This irresistible weapon will turn the tides." Actually, letters by Al-Husayni on "German vengeance weapons" written to his Arabian collaborator Shakib Arslan were intercepted by allied services in 1944.

N.Pastorius
Rotterdam