Hitler's Bombe: Die geheime Geschichte der deutschen Kernwaffenversuche (review)

Rainer Karlsch's book is controversial, but this is to be lauded. He has had the courage to bring the methodical patience of a trained historian to a subject, the German atomic bomb, so often abandoned to crackpots. Some authors allege that an alliance of the SS, American intelligence, and the NKVD and KGB sequestered top-secret plans for a German bomb after the war. In league with any and all "dark ops" imaginable, they kept this secret from the postwar world, for nefarious purposes that are as difficult to decipher as they are promiscuously related to other conspiracy theories. German scientists, on the other hand, argued that they had "sabotaged" Hitler's bomb project so as not to place the sublime knowledge of physics at the service of warfare. Mark Walker's books and articles are a sensible antidote to tales such as these and convincingly argue that Germany's physicists and military establishment abandoned any serious push for an atomic bomb. Army weapons experts diverted scarce resources elsewhere. Who could doubt they were right? (Can anyone seriously imagine Oak Ridge's uranium diffusion plant set up in territories subject to massive aerial bombing?) German scientists worked on reactors but failed to develop these to any great extent either.

Now, however, Karlsch presents convincing evidence that the Third Reich was indeed well on its way to some kind of nuclear device. The SS even seems to have tested one in Thuringia. Karlsch's findings are not designed to refute Walker; in fact, the authors collaborated on a joint article in Physics World in 2005. Karlsch has uncovered evidence of a parallel but previously overlooked research and development project. He bases a great deal—but by no means all—of his evidence on oral testimony. As such, it is extraordinarily slippery. Nevertheless, by cross-referencing postwar interviews with primary documents and 1940s scientific publications—all embedded in the context of the rapidly collapsing German war effort—Karlsch develops a convincing narrative, layer upon layer.

Heinrich Himmler exclaimed at the end of January 1944: "Explosive devices will appear all of a sudden, due to the progress of technology. The effectiveness and speed of these devices will put our newest explosives for the Vengeance Weapons [i.e., the V-1 and V-2 rockets] in the shade" (p. 193). At issue seems to have been a relatively small nuclear device using shaped charges, a notable German area of expertise developed for weapons systems like the "Panzer-Faust," a compact antitank weapon.

Experienced historians are always skeptical of Himmler's statements, for he was inclined to spasms of enthusiasm over any "wonder weapon." This usually had little to do with deployable systems, and even less with what Germany's military-industrial complex was doing. Still, Karlsch marshals far more than the ebullient eruptions of Himmler. Most intriguing, both Germany's allies and its enemies seem to have agreed that something was going on. An Italian war correspondent, Luigi Romersa, reported to his government that he had witnessed an extraordinary weapons test. Was this simply information fed by the Germans to shore up a wavering ally? The Chief Department of Intelligence of the Red Army thought not. In archives of the former Soviet Union, Karlsch has uncovered a 23 March 1945 report that urgently warns of "two large-capacity bomb explosions in Thuringia. . . . In addition, a massive radioactive effect was observed. . . . Without doubt, production of such bombs in sufficient quantities [will be] capable of slowing down our advance" (p. 221).

What did it all amount to? The Germans never deployed the weapon. Contemporary radiological investigations remain inconclusive about the test site. Nevertheless, Karlsch definitely proves that the German bomb is a bigger story than previously imagined. His findings also fit with what we know of institutions like the SS, which forced the pace of numerous projects to create "wonder weapons" at the end of the war. Some, like the V-2 rockets or the Me-262 jet...