After World War 2 it came to light from personal memoirs and collections of papers, which were not seized by the Allies, that Nazi scientists Dr Erich Schumann and Dr Walter Trinks filed up to 40 workable patent applications in wartime Germany from 1941-1944 for what we nowadays term tactical-nuclear weapons.
Further light was given in post war articles by, or interviews with Dr Kurt Diebner and Dr Walter Trinks. Their wartime designs were amazingly credible. They were far more sophisticated than the Allied bombs dropped on Hiroshima and Nagasaki requiring only sub-critical quantities of fissile material. Their designs were also adopted post war by the Americans in the so called Swan Device of 1956.
Further light was given in post war articles by, or interviews with Dr Kurt Diebner and Dr Walter Trinks. Their wartime designs were amazingly credible. They were far more sophisticated than the Allied bombs dropped on Hiroshima and Nagasaki requiring only sub-critical quantities of fissile material. Their minature nuclear weapon designs were inspiration for the American Swan Device of 1956. Diebner was hired by Operation Paperclip and went to USA to guide the US nuclear program, working closely with Dr Freidwart Winterberg. Trinks went to France after WW2 helping to develop their nuclear weapons program.
Corroboration by Stockholm Signal:
Corroboration emerges from various directions. For example the so called Stockholm signal. An enciphered diplomatic signal from Japan's embassy in Stockholm back to Tokyo sent in five parts in December 1944. It reported Germany's Uranium atom splitting weapon with an explosive of tremendous force. The ULTRA decrypt of this signal gathered dust in US military archives until 1978 when it was declassified. There is currently no explanation reconciling the contents of that signal with the conventional view that Germany never had nuclear weapons. 
Until 2005 few people seriously questioned the accepted historical account that Nazi Germany failed to produce an Atomic Bomb, but with the publishing of Hitler's Bombe, (2005), by author Rainer Karlsh, this accepted account of history is now widely challenged.
Karlsh astonished the world when he revealed evidence from various witnesses of a nuclear test on the Baltic Island of Rugen in October 1944, including press correspondent Luigi Romersa who only passed away in 2007.
Karlsch claimed these tests in October 1944 were followed by two more nuclear tests at Ohrdruf Concentration Camp in March 1945. He produced Kremlin archives to prove that Soviet intelligence reported the Ohrdruf tests to Stalin. Karlsh also produced the account of then still living witness Claere Werner custodian in 1945 of Wachtel Castle near Arnstadt, whose interview is available on Youtube.
A 1943 OSS report found in the Woods Memorandum to US secretary of State Cordell Hull also refers to a series of nuclear tests in the Schwabian Alps near Bisingen in July 1943. These tests are corroborated by seismic records.
Nature of the Nazi Weapon
The weapons allegedly weighed 4-5 kilograms and used the principle of crushing Lithium into Deuterium at huge pressures & temperatures to generate fast neutron X-rays, known as a plasma pinch. Ironically this method was also known to the Manhattan Project in 1942 when the exiled scientist Enrico Fermi tried to persuade the Americans to develop this concept. The Manhattan Committee rejected a minaturised nuclear warhead with plasma pinch technology as too technologically challenging.
These plasma pinch X-rays caused a fusion reaction between molten Lithium from the hollow charge liners and Deuteride coating the fissile target. The neutron flux was high enough that it created uniform criticality throughout the whole fissile mass, thus ignited fission in small, sub critical quantities of bomb grade Uranium. The fissile target is understood to have been a mere 150 grams of Uranium 233. This method avoided the need for a massive Uranium 235 enrichment project. The quantity of fissile material required were much more modest than the enriched material required for Allied nuclear weapons and in turn demanded a project much smaller than Oak Ridge for harvesting fissile material.
Why if the Nazis had nuclear weapons, did they still lose the war?
The most logical explanation appears to be Churchill's threat to drop Anthrax laced cattle cakes over Germany in August 1944. Germany had no antibiotics and would have faced starvation within 2 weeks had Anthrax been used. Even earlier than this however USA at the beginning of July 1944 threatened Hitler through the German Legation in Lisbon that unless he sued for peace within 6 weeks Dresden would face attack with a nuclear bomb. In the light of continuing efforts by the United States to keep references to these matters classified, or suppressed, Nazi acquisition of nuclear weapons cannot simply be dismissed out of hand.
Frustrated nuclear attack on New York?
There does however appear to have been at least one attempt to attack USA with nuclear weapons when a lone six engined Junkers aircraft was downed in shallow coastal waters south of Owl's Head, Maine about 17-18 September 1944. The bodies of three German aviators were recovered nearby on 28 September 1944 and were taken to the Rockport Coast Guard Station. It appears they were buried nearby with a small stone cairn erected over their grave. Locals were warned by FBI and Secret service never to repeat their sighting to anyone, thus this pivotal attack on USA has gone unnoticed in all of 65 years. Could it be that the failure of Hitler's Last Trump arose not from a failure to build a nuclear weapon, but from the inability to deliver the weapon over it's prime target, New York?
This is a chart of New York prepared for Goering in 1943 describing the effects of a nuclear air burst over the city. Bombing New York was a major obsession for Hitler. English text has been added over the chart by a more modern author:
Another justification for nuclear secrecy was raised in the so called Monsanto Report to A.H. Compton, where the authors comment on the ethicacy of releasing "useful information" in their report and Nazi records.
Authors note that, "...anyone knowing what is in the German reports can establish a chain reaction provided he has sufficient material."
If that statement is correct then anyone with a truly enquiring mind should be curious to know why the Nazis did not succeed in the race for the Bomb, nor indeed why they lost World War Two.
My Personal Commentary
In the Postwar era the free press and more lately the internet has helped us to understand that Governments do lie to us and that history books can't be relied upon. Is there some other explanation how World War Two came to an end?
Those not interested need read no further, and relief is just a click away because the internet is full of conventional accounts of history to occupy their time. Perusal of my website is entirely optional.
As this website takes shape, I intend to add successive webpages to enlighten readers to the latest and in many case most controversial information coming to light about the the real Nazi Atomic weapons project.
 Japanese Diplomatic signal intercept 12 December 1944 (Magic decrypt) Trans 14 Dec 44 (3020-B),
"Stockholm to Tokyo, No. 232.9 December 1944 (War Department), National Archives, RG 457,
SRA 14628-32, declassified October 1, 1978 (SRA = Japanese Attache)
 Rainer Karlsch - Hitlers Bomb, (March 2005)
 Monsanto Report, 8th November 1945, authors A.W. Weinberg & L.W. Nordheim (NA, RG 371 -
© Simon Gunson (non-commercial reproduction permitted, but please cite source)
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