Nuclear Education: Subcritical and Microfission Explosives
We have entered a new nuclear age, one far more dangerous and deadly than the Cold War with its megatonnage held in check by the doctrine of Mutually Assured Destruction. In this new age, the nukes are many times smaller, and the chance of their use many times greater.
Why? for the simple reason that it is impossible to hide the use of a megaton class ‘city buster’ (people would notice the smoking hole where the city once stood) but it is possible to hide the use of small nukes. This ability to get away with their use makes their use inevitable.
Even worse, modern designs can be built simply and cheaply using any and all grades of fissile material which means that Nuclear Non-Proliferation is a forlorn hope and any country can afford to build them.
We present here the hard science behind modern small nukes in the hope that it makes the penny drop that these terrible weapons are within reach of all of the world’s bad guys and that spurs the good guys to do something about this most dangerous situation.
Considering that existing high-yield thermonuclear weapons will remain the principal component of strategic nuclear arsenals for quite a long time, it is likely that the first fifth-generation nuclear weapons to be developed by the nuclear-weapon States will be highly miniaturized explosives with yields in the 1 ton to 1 kiloton range, i.e., within the gap that today separates conventional weapons from nuclear weapons.
These “low-yield” nuclear weapons will not be considered as “weapons of mass destruction” and their construction will be possible for all countries, including the non-nuclear-weapon States.
In the following section, we will examine concepts that are under active scientific investigation and which have a strong potential to be developed into such new weapons.
Subcritical and Microfission Explosives
To address the question of subcritical explosives, it is useful to recall some elements of neutronics. If k∞ is the average number of neutrons produced by fission (and possibly by other processes) per neutron absorbed in an infinite medium, and l the number of escaping neutrons leaking out of a finite assembly, the effective neutron multiplication factor, or criticality factor, is: k = k∞ − l.
The average lifetime of a neutron in an absorbing medium, i.e., the time τa between its production and absorption, is: λa τa = v where λa is the absorption mean free path and v the average neutron velocity. For each generation of neutrons, that is, for each interval of time, the number n of neutrons in the assembly is incremented by n(k − 1).
The time rate of change of the number of neutrons is, therefore, k−1 dn = n = αn, dt τa where α is called “Rossi α”.5 For k and τa constant, and with n(0) the initial number of neutrons, the solution of this equation is then exponential:
In a nuclear explosion, α is a function of time because all parameters, such as the geometry, the density, and the nuclear properties of the fissile material, change with time during the chain k−1 n(t) = n(0) exp ( t) τa.
When the criticality factor k = 1, the number of neutrons remains constant, and the assembly is called “critical.” This is the normal operation mode of a nuclear reactor in which one has a stable chain reaction. When k > 1, the assembly is “supercritical,” and the number of neutrons increases exponentially with time. The chain reaction is divergent and leads to the explosion of the assembly. Finally, when k < 1, the assembly is “subcritical,” and the number of neutrons decreases exponentially with time, which implies that there is no self-sustaining a chain reaction.
This does not mean, that a subcritical assembly cannot be used to produce nuclear energy or to make a nuclear explosion. In effect,since at each generation of neutrons, the number n of neutrons in the assembly is multiplied by k, the total number neutrons produced by an initial number n(0) is n(0) n(∞) = n(0)(1 + k + k 2 + k 3 + …) =1−k.
This series converges for k < 1. Thus, for a subcritical assembly, the initial number of neutrons is multiplied by a factor G = 1/(1 − k). For if k is close to 1, this gain factor can become very large. Hence, by injecting a sufficient number of initial neutrons into a subcritical assembly, it is possible to generate a large number of fissions, and thus to release a considerable amount of nuclear energy. This technique is called subcritical burn.
To understand the potential advantage of this method for making a fission explosive it is important to recall that in a normal fission bomb the plutonium has to be made highly supercritical so that the divergent chain reaction can fully develop. This means that the plutonium has to be compressed much more than would be required to just reach criticality.
For example, a 1 gram plutonium pellet becomes critical at a density equal to about 100 times its normal density. However, to produce a significant yield, it is necessary to further compress the pellet to increase its density by an additional factor of about 10.
On the other hand, in a subcritical device, it is sufficient to reach k ≈ 1, an advantage that is especially significant for micro fission explosives containing less than a few grams of fissile materials. However, compared to a normal nuclear explosive (in which a few neutrons are in principle enough to start the chain reaction. In a first approximation, α ≈ vχN0 σf (ν − 1), where σf is the fission cross-section, ν the number of neutrons per fission and χN0 the fissile nuclei number density, with χ the compression factor reaction) the disadvantage of a subcritical device is that it needs a very powerful neutron generator to supply the relatively large number of initial neutrons n(0).
The results of a simulated subcritical burn of small pellets of plutonium having weights of 14, 70, and 700 milligrams each. With the goal of determining (as a function of compression) the number of initial neutrons required for 100 percent burn; corresponded to the release of 240, 1’200, and 12’000 kg of fission energy.
Obviously, yields of between 0.24 and 12 tons of TNT are of considerable military interest. Moreover, in the subcritical burn, the quality of the fissile material is of little importance: reactor-grade plutonium is just as good as weapons-grade plutonium.
With a fissile material density on the order of 103 to 104 g/cm3, i.e., for compression factors on the order of 100 to 1’000, the number of initial neutrons required for the complete burn is about 1018. In that same range, the compression work to reach the necessary plutonium density is equivalent to the energy content of about 100 g of chemical explosives.
Assuming a 10 percent conversion efficiency of the chemical energy into compression work, this means that with 1 kg of high explosives and less than a gram of plutonium, it is possible to produce a very compact fifth-generation fission explosive with a yield of several tons.
It can be seen that at a sufficient compression level the number of initial neutrons decreases dramatically. This is because when k → 1, the gain increases as the assembly approaches criticality where, in principle, a single neutron is enough to start a chain reaction. This leads to the idea of micro fission explosives in which a small pellet of fissile material is driven to criticality by a laser.
At first, it was thought that this method could be used to ignite fusion materials, and thus to provide an easy route to ICF and almost pure-fusion explosives for military purposes. But it was soon discovered that a major difficulty with micro fission was the problem of the initiation of the chain reaction.
Indeed, in micro fission, the stagnation time of a highly compressed pellet is so short that the probability of spontaneous fission releasing an initial neutron is negligible. Moreover, the use of an external source of neutrons is almost impossible because it is very difficult to deliver and focus a stream of neutrons onto a very small target at just the right time.
Hence, it was suggested that the initial neutrons could come from DT fusion reactions produced in the center (or in the reflector ) of the fissile pellet. However, as with ICF pellets surrounded by a heavy tamper to increase the confinement time, it is always better to work with a pure fusion target than with a hybrid fusion-fission target.
This is because DT is easier to compress than any heavier material, and because the specific energy content of DT is higher than that of fissile materials. Therefore, it is much more attractive to develop micro fusion rather than micro fission devices. Nevertheless, a micro fission device could be used to implode a more powerful fusion device.
Compared to micro fission, the practical problems of subcritical burns are less acute. For one thing, the compression work can be ten to a hundred times less than the energy necessary to reach criticality. Moreover, since subcritical burn does not depend on a self-sustaining chain reaction, but on an external supply of neutrons, 100 percent fission burn efficiency can be achieved in principle. Finally, contrary to micro fission, the subcritical burn is not restricted by the CTBT.
In summary, a critical or subcritical micro fission device can in principle serve as a low yield explosive or as a primary to compress higher yield fission or fusion pellet. To do that, it is necessary to find a means to achieve the required compression, as well as a suitable source of neutrons to initiate the fission reactions, two things for which there was no practical solution in sight until recently.
The problem with compression is that the maximum pressure and the detonation velocity of existing chemical explosives are not high enough to compress fissile materials to the required densities. Using a very sophisticated implosion technology, the maximum compression factor achievable is about 10.9. To increase the density of uranium, or plutonium, by another factor of 10 would require a “super-explosive” at least 45 times more powerful than any existing high explosive.
Compression to about 100 times normal metal density would, therefore, require a system of laser or particle beams — or the use of magnetic compression. All isotopes of plutonium are fissile for fast neutrons, e.g. and the problem of pre-initiation is absent in a subcritical burn.
Notes.
A. To turn the concept of microinfusion into practice, two major problems are the compression method and the initial source of neutrons.
B. The yield of non-nuclear warheads of modern missiles and gravity bombs is limited by weight to a maximum of about 0.1 to a few tons of TNT.
C. The smallest amount of plutonium that can be made critical in a fast assembly is about 100 grams.
For P u / 235 U
Nuclear fuel: HH DD DT LiD
Mass 2 4 5 8 239/235
Density [kg/ ] 0.08 0.17 0.22 0.80 19
Yield-to-weight [kt/kg] 21,400 80 80 50 17
Yield-to-volume [kt/ ] 1,700 13 18 40 320
Table 1.1: Normalized maximum energy contents of nuclear fuels.
Thermonuclear explosion timing [nanoseconds]
Primary:
- Compression by chemical high explosives (HE) 10’000 – 50’000
- Rayleigh-Taylor instability (HE/Pu boundary) 5’000 – 10’000
- Rayleigh-Taylor instability (Pu/DT boundary) 100 – 400
- Chain reaction 150 – 300
- Rayleigh-Taylor instability (Pu/DT mixing) 2-8
- Boosting (DT burn) 1-4
- X-ray pulse 10 – 50
- Fission core disassembly 10 – 50
- Full disassembly 500 – 2’000
- Primary/Secondary:
- X-ray arrival time 1
- Neutron arrival time 20
- Shock wave arrival time 1’000
- X-ray thermalization within hohlraum 10
Secondary:
- Ablative compression 100 – 500
- Chain reaction (sparkplug) 10 – 30
- Thermonuclear burn 3 – 20
- Fusion fuel disassembly 3 – 20
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Mark Tapley
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Veterans Today is a MSM disinformation outlet for right wing propaganda. Note that in the more than 75 years since the fake atomic attacks on Hiroshima and Nagasaki not one country has used an atomic bomb other than in a fake test as the article I post below will outline with photos. In the Book “Death Object, Exploding The Nuclear Weapons Hoax” Akio Nakatoni gives detailed analysis the conventional attack on the two Japanese cities, with photos. Atomic weapons are used as part of the Hegelian dialectic in order to frighten the goyim into surrendering their natural rights before the specter of nuclear Armageddon just as the fake virus is medical propaganda to instill pathogenic anxiety and dependence on the allopathic fear mongers. The nuclear hoax is not just a great propaganda tool for the Zionist elite to instill fear in the herd but another great money laundering scheme such as was used with the fake Apollo mission to Stanley Kubrick’s front screen projection studio.
http://mileswmathis.com/trinity.pdfhttp://mileswmathis.com/trinity.pdf
https://www.youtube.com/watch?v=BwspVAbfEWk&t=210s
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Joseph Olson
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Your opinion is unfounded, the US conducted over 2,500 nuclear tests. A family friend was sailor, ordered to watch the Bikini Island Hydrogen bomb test, described in detail before dying of nuclear radiation cancer 20 years later. My articles at VeteransToday >
“Unequivocal 9/11 Nukes” and “Exposing NIST Jenga Game”
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Mark Tapley
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Hello Olson:
You say my opinion is unfounded and then offer nothing to refute it except the usual family friend or acquaintance as another anecdotal testimony. I furnished an article with photos of the fraud in progress. You claim my opinion is unfounded but believe the Zionist controlled narrative. The same group that are now perpetrating the greatest crime against humanity with the fake vaccine.
I could go on but will suffice to say that I am not surprised that your article was published in the Veteran’s Today propaganda rag. You also further discredit your self by making the ridiculous claim that nukes were used in the standard thermite controlled demolition of 911. The squids from the charges are even evident as they were set of in sequence floor by floor.
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LLOYD
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Having been to the Nevada Test Site, Nukes happened. I guess the Japanese faked all those photos. I am beginning to believe you are just posting bizarre ideas, like the Zionist World Order, to obtain gain attention on the Web and start arguments. Sad that PSI does not ask you to seek some counseling.
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JaKo
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Hi there,
This article is a stranger — as I understood it, there is a need to force Plutonium or what-not to 100x of its density, yet there are no known methods (e.g. chemical explosives powerful enough) to do the job. Akin to: “yes we could have a time machine, only if we could reverse or advance the time…”
OTOH, we could have a real atomic fission device, tested and true, to do that liddle job. Oops, that wouldn’t be “sub-critical or micro-fission” though.
Thank you, JaKo
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LLOYD
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Having been to the Nevada Test Site, Nukes happened. I guess the Japanese faked all those photos. I am beginning to believe you are just posting bizarre ideas, like the Zionist World Order, to obtain gain attention on the Web and start arguments. Sad that PSI does not ask you to seek some counseling.
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Mark Tapley
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Helio Lloyd:
So you have wasted time at the fake test site. They have lots of pictures of Oppenheimer and other big shots standing at the Trinity site with zero protection shortly after the “tests.” It turns out that there were no tests before the fakes were deployed on the Japanese cities as I cover in the comment to Herb. However since then they have needed extensive testing. It seems to not occur to the simps that it is easy to simulate a “nuclear” explosion just like a fake walk on the moon. The nuclear armageddon narrative has to be maintained just like the holohoax, the fake virus and the global warming narrative.
As to the Zionist network I refer you Bill Clinton’s History Professor at George Town, Carrol Quigley who documents the formation of the Anglo Zionist organization in his books “The Anglo American Establishment” and “Tragedy and Hope.” A recent book by British historian Jerry Docherty titled “Hidden History, The Secret Origins of the First World War” is heavily foot noted and chronicles the formation of the Zionists syndicate under the leadership of Alfred Milner. Some of the members included Edward VII, Rothschild, Lloyd George, Churchill and many more. After WW1 Herbert Hoover sent a team of researchers throughout Europe to gather up all relevant documents that could incriminate them. But they could not get everything.
Lloyd your psychoanalytic abilities apparently even exceed the those of Sigmund “Fraud” himself, the father of this particular racket. Also an ardent Zionist Jew. Perhaps you should take up your own practice in counseling since even Freud never gave opinions on people he had not met.
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Mario M
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Besides Akio Nakatani book and Miles Mathis articles, there is an interesting analysis from Anders Bjorkman,
https://heiwaco.tripod.com/bomb.htm . According to him no nuclear bomb has ever been built, since it is phisical impossible, whereas in nuclear plants there are no esplosive reactions. The two japanese cities suffered traditional carpet bombing.
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Herb Rose
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Hi Mario,
Anders is incorrect. His contention that since explosions don’t occur during transportation and storage is also true of conventional bombs. Bombs need fuses and detonators (initiators) to explode. In a atomic bomb there is a critical mass where the concentration of emitted neutrons becomes an uncontrolled chain reaction causing more atoms to split releasing more neutrons. Until the critical mass is reached the mass just decays at its half life rate. In a nuclear reactor the fuel pellets can be handled because they are composed mostly of U-238 not U-235. When the fuel rods are brought together in the reactor the neutrons emitted by the U-235 become more concentrated converting U-238 to U-235 producing a controlled chain reaction and the fuel rods become highly radioactive. In a bomb the U-235 is below the critical mass emitting neutrons. When a bullet of U-235 is fired into the mass it exceeds critical mass and an uncontrolled chain reaction occurs causing the explosion.
At Hiroshima when the air raid signal sounded people did not go to the shelters because there were only 2 bombers in the sky and they assumed they were just doing reconnaissance. There was no carpet bombing or craters.
Herb
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Mark Tapley
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Hello Herb:
Akio Nakatoni says that many people have worked out the formula used by the scientists at Los Alamos, including him. He states that the explosive chain reactions and fast fission does not work. The fact that no government has used one of these bombs in over 75 years other than in fake atomic simulations with conventional explosions made to appear to be atomic should ring a bell.
The Mathis article brings out lots of inconsistencies in the usual government fake narrative such as the fake trinity blast where Oppenheimer and others are walking around the site with no protection a couple of weeks after the blast. The Trinity “test” was only three weeks before the attack on Hiroshima. A little quick, don’t you think? The Japanese already had no defense, their navy and merchant marine were all at the bottom of the ocean, oil reserves were gone and the population was beginning to starve. Better hurry this thing up and bomb them.
The Trinity test was supposedly a plutonium device that claimed to be used at Nagasaki. So that means the first uranium bomb that was allegedly used at Hiroshima was never tested. So if these bombs that did not really need to be tested before deployed, how is it that since then they have conducted thousands of “tests.” It’s just more propaganda to fool the gullible that believe whatever the Zionists MSM tell them like with the fake virus and climate change.
The whole atomic money laundering operation is very similar to the NASA Apollo moon mission to Kubrick’s front screen projection set. And its no big deal that all the ALL of the original “moon footage” was accidentally erased in the 80’s. It was only another 100 billion in1960’s dollars tax money.
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Herb Rose
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Hi Mark,
As I’ve said before, a nuclear bomb blows the radioactive material away from ground zero. A neutron bomb is designed so that troops can occupy the bombed area twenty minutes after the explosion because neurons decay in ten minutes.
The testing for the Uranium bomb was done under a stadium in Chicago. They increased the amount of uranium to determine what critical mass would produce an uncontrolled chain reaction. They knew a chain reaction occurred but needed to find the mass to create a bomb (uncontrolled). Their safety measures were students with buckets of heavy water ready to kill the reaction if it started to go critical. Since then tests (plutonium and hydrogen bombs, not uranium) have been done to refine design, resulting in the size and weight of the bombs shrinking from the huge Fat Boy” to where multiple warheads can fit in the tip of a missile or in a bomber. The first hydrogen bombs used atomic bombs as triggering (compression) devices. This is now done with conventional explosives.
You should be thankful that these bombs have not been used since the end of WWII. You do know that most of the bombs used during the Iraqi wars were bombs built during WWII don’t you?
The formula for uranium bomb is simple. When the nucleus of a U-235 atom is struck by a neutron it splits producing 3 neutrons as well as two smaller atoms. This is the chain reaction, 1 neutron produces 3 protons which produce 9 neutrons which then produce 81 neutrons. Since some of the neutrons escape as radiation you need enough mass to have the reaction escalate into an explosion. The size of the explosion depends on the mass of uranium and the design.
Even though the Japanese had been bombed into oblivion they would not surrender because of their belief that the emperor was a god. It was only after they received assurances that he could remain as a figurehead (he should have been tried as a war criminal) that they surrendered. You can understand how religious beliefs can negate all reason and the acceptance of reality.
Herb
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Mark Tapley
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Hello Herb:
The fake tests are all over the place as far as craters. The fact remains that after the supposed test of the plutonium bomb at Trinity was only three weeks before a different uranium bomb was claimed to have been dropped on Hiroshima. That means it could not have been tested. Even the most mundane of products manufactured usually take months to test. The “atomic” bomb results at Hiroshima and Nagasaki were identical to the other 66 cities that had been destroyed. After the fake Bikini test it was claimed that the radiation would preclude the return of the natives for decades but no Japanese were excluded from the “nuked” cities. I have already detailed the obvious lack of “atomic”: destruction of the plant life and infrastructure.
Since no nukes have been deployed other than in the fake tests similar to the fake Apollo missions, I don’t think we have to be too concerned about it now after over 75 years. It is not reasonable that no atomic weapons would have used over so long a time if they were legitimate. Nor is it logical that we would not have put men on the moon after more than 50 years since 1969.
The Japanese with all of their major cities in ruins, no defense from air attack, hardly any oil reserves, their navy and merchant ships sunk with no way to even get their stranded troops off of far flung islands and starvation setting in on their people, I kind of doubt that atomic bombs would have been used even had they worked. The atomic weapons are merely a propaganda tool like the fake virus. Zionist Truman had already been informed by the Generals that they were running out of targets to bomb.
The Japanese had been trying too surrender for over six months. The reason it was delayed was so that the Soviets could defeat the Japanese in Manchuria and then be brought into the war effort as our great allies against mainland Japan. This set up the coming Korean situation and was an excuse for 60 ship loads of military hardware to be donated by the Zionist controlled U..S. to the Soviets along with large stockpiles of Japanese equipment in Manchuria. The Soviets were brought into the war against the mainland two weeks before the Americans finally accepted Japanese surrender under the same conditions as originally proposed. The emperor figure head is just a decoy. Now the Japanese opposition to communist (Zionist) expansion was eliminated in China, as had been accomplish in Europe with the defeat of Germany. All that had to be done at that point was cut off all aid to the anti communist forces of Chang Kai Chek and the Hegelian dialectic was accomplished. Then it would be time to flip the Russians around from out great allies to our deadly enemy for the Cold War scam. See James Perloff for more on this.
Best regards, mark
Herb Rosr
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Hi Mark,
Your history is bad. The date of the Russians entering the war against Japan was set at the Potsdam conference when the defeat of Germany was near. They waited to the last possible date to tell the Japanese (who were trying to use them to broker a surrender for the two months that wads stipulated at Potsdam)) that they would not help them negotiate a surrender and declared war. They had their army (supplied by America) sweep through Manchuria and gain the territory they had wanted in 1904.
It was on learning that the Japanese were going to attack America that allowed Stalin to pull the Siberian troops from the Manchurian border (which the Japanese had controlled since the end of the 1904-05 war with their defeat of Czarist Russia helped establish the communist party) and prevent the Germans from taking Moscow.
It was the Japanese attack on Pearl Harbor that led to Germany’s defeat. After Hitler declared war on the U.S.hundreds of ships and supplies went to Russia and it was these supplies that allowed the Russians to defeat Germany. Before that one rifle was issued to every third soldier and the soldiers with no weapons were told to get their weapons from the ones who were killed (machine guns were set up to prevent them from retreating). Without having been able to shift armies from the Manchurian border Russia would have been defeated by Germany.It was Hitler’s allies (Italy in North Africa and Japan in the East) that cost him the war.
As I said the Japanese refused an unconditional surrender to preserve the emperor and Russia having insisted on Germany’s unconditional surrender (German generals had tried to surrender to the western allies but were rebuffed) honored this commitment because it was evident that Japan was defeated. The Japanese arms had not progressed since the beginning of the war and their tanks, rifles, grenades, machine guns, airplanes etc were no match for the armaments the Russians had and were as useful as a Civil War musket would be.
I suggest you read some history that is based on reality not ones that support your pre-existing prejudices.
Herb
Mark Tapley
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Hello Herb:
The Soviets spent weeks moving material from the west to to Chinese boarder and then launched the attack on the Japanese after the American bombing of Hiroshima and Japan. As I mentioned the Japanese had been trying to surrender for six months and got the same terms they originally negotiated.
Germany’s defeat was due to the sabotage by Hitler (former elected official of Jew Kurt Isner’s Bavarian communist party). This is best illustrated by him letting the BEF float back across the channel but continued through the Russian campaign that the Germans could have easily have won had Hitler not divided his forces and then shifted them around and stalled them whenever possible.
The main factor in all of this contrived war is that Jewmerica and the international bankers put the Soviets (Bolshevik Jews) in power to begin with. Of the original Soviet government of 486 officials, all but 16 were Jews. They even had a couple of Russians. It was only because of massive agricultural, industrial and financial that they remained propped up for 70 years. This massive aid is documented by Hoover Institute researcher Anthony Sutton. When this paper tiger who had been our great Allie and then was flipped around to become out deadly enemy finally ceased the Cold War scam in 1989, they were producing less grain than 70 years earlier when under the Czar. In the 1950’s the Soviet Union had less automobiles than the country of Spain that was noted for it’s backwardness.
Jacob Schiff financed the Japanese build up for the 1904 war. The Zionist Jews attempted to overthrow Russia but failed in 1905. Russia began to make lots of progress at this time and the Zionists knew that they had to overthrow the Czar soon or else it would be too late. The same Jacob Schiff put up 20 million (in1915 dollars through Kuhn and Loeb) along with other Jew controlled banks to overthrow the country. Lenin was sent in from Germany and Trotsky with 200 Zionist Jews came in for N.Y. city and were initially detained in Canada. Only the personal intervention of Zionist puppet Wilson got them released.
After the phony Cold War, 911 was instigated along with fake WMD’s at which time the 2.3 trillion in defense money was reported missing by Rumsfeld the day before 911. That was forgotten by our Jew MSM now occupied with the cartoon airplanes going through steel and concrete buildings. The path was now laid for more massive military appropriations for the new “War On Terror” for Greater Israel.
Mark
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