Exactly. Trav is talking complete nonsense.Weapon-grade U-235 HEU is just 1/144th of all natural uranium.Between 48kg and 60 kg was used in the Hiroshima bomb, so let's call it 55kg, and that's;55kg * 144 = 7.9 metric tonnes of natural uranium per A-bomb core.With losses included let's call it a conservative 10 tonnes of uranium per bomb.So you can build 50 Hiroshima gun-type HEU nukes with a mere 500 tonnes of uranium. That ain't no mountain, that's about one train-load of yellow cake to convert to gasify into uranium hexafluoride.But there is nothing to stop you designing a far smaller and lighter symmetrical core implosive HEU munition that uses substantially less HEU than that original (extremely wasteful oversize and very heavy) gun-type Hiroshima HEU design. That design was only developed as a fall back in order to be absolutely sure the US would have a working A-bomb that absolutely would go bang (and this didn't even need to be tested before being used in combat, so confident were they that such a super wasteful design would work). This was because no one was certain they could get the much more complex and smaller plutonium implosion core used at Nagasaki to work. As it turned out the Trinity implosion test made it clear the Plutonium approach could also work acceptably reliably. Thus a modern HEU munition won't use a gun-type assembly, but a high-density compaction of an imploding HEU core instead, to assemble a lower weight critical mass sphere (rather than a non-compressed crude mechanical juxtaposition of two parts slamming together that combined make up a transient critical mass assembly). This means you may need only 5 tonnes of uranium per HEU bomb, so they can be generated much faster (or else, in greater secrecy) than before, and these implosion designs then also incorporate all the very desirable physical and electronic safety constraints against the possibility of unauthorised detonation.This HEU path is clearly the optimal path to a small nuclear arsenal.Thus compact tactical-yield HEU weapons in the 0.5 to 5 kiloton range are eminently viable, cheap to make, easy to design plus zero-yield test, and relatively simple to manufacture maintain and store safely. Yet safe to move about and very stealthy. Plus a small layer-cake core design with an enlarged tamper could be expected to approach 25 to 35 kiloton yields. These are more than sufficient for anything below strategic-level EMP attack as that would require a constantly replaced stock of tritium created in a reactor, in order to reliably reach yields >50 kilotons (plus these would require actual full-yield testing, and that would signal that you're developing a strategic EMP warhead, but this step may eventually be taken, after several years, as it's pretty clear the "Vela Incident" in the Southern ocean, on Sept 22 1979, was Israel proof-testing a strategic-yield warhead design capable of a strategic EMP strike).Seriously, on an industrial scale of production, that is fuck all, and can be easily acheived secretly over a period of years, let alone decades, if your enrichment technology is sufficiently conpact, affordable and efficient.Laser enrichment is now a reality since Australia developed SILEX during the mid-1980s, when it was operating two separate secret laser enrichment programs simultaneously, right after closing down a secret gas-centrifuge enrichment plant in 1986, that had been operating since well before 1983. And an even earlier one that was setup in 1965 and shut down before 1973 as the NPT was ratified.This laser enrichment process demonstrated efficiencies levels that were said by SILEX to exceed 20 times the efficiency of the then current operational US uranium enrichment techniques in 2001. Plus it's physically much smaller and unobtrusive, lower cost, solid-state (not mechanical) so low maintenance, and uses much less power than earlier enrichment techniques, requiring far fewer staff, and thus far less chance for discovery, and a greater capacity to maintain security and access. Australia developed SILEX in secret, in plain sight, at an IAEA safeguarded facility, and was never discovered (none of the four enrichment programs were, over 3 decades ... so much for the safeguards), and other than the use of uranium hexafluoride, the SILEX process didn't actually resemble any form of uranium enrichment processing. Thus no one knew about any of it until Canberra was ready to reveal it's existence to the US Govt in about 1996. In 1994 the other laser enrichment program was disbanded, at the same site, and some of its equipment was re-used in the supposedly 'private' SILEX process.This technology will now have been replicated by others, or very soon will be, and will be operating elsewhere, in secret. It is believed Israel also developed a less efficient and more problematic laser enrichment process, but it also is way ahead of first and second generations of uranium enrichment technology, that all the other nuclear powers used to make HEU.So things have really changed and HEU is now potentially the fastest cheapest and most stealthy way to produce weapon-grade fissile material, plus uranium is abundant, and many countries have extractable deposits, as mining and extraction techniques have also reduced costs and increased the speed of obtaining national uranium stockpiles.So creating HEU is hardly a major technical challenge any more. The US and Russia each created very large stocks of weapon-grade HEU by the mid 1960s. The British also were pumping out weapon-grade HEU amazingly quickly during the late 1950s. Capenhurst"Britain's indigenous supply of enriched uranium is supplied by the gaseous diffusion plant at Capenhurst, originally the site of a Royal Ordnance factory, 25 miles from Risley in Cheshire. Although an enrichment plant was authorized in October 1946, the site was not selected until early 1950. Capenhurst made its initial start up in February 1952, but did not successfully enter operation until 1953 (producing low enriched uranium), and did not produce highly enriched uranium (HEU) until 1954. The plant was given successive upgrades during the fifties, reaching a military significant capacity of 125 kg of highly enriched uranium a year in 1957, and much higher levels in 1959 (as much as 1600 kg/yr, or an enrichment capacity of 325,000 SWU/yr). Capenhurst operated as a source of HEU at full capacity only until the end of 1961. Most of the stages were shut down at that point and the plant converted to low-enriched uranium production for civil reactor use. The 1996 SIPRI estimate was 3.8-4.9 tonnes of HEU being produced, almost all of it in 1959-1961."- Carey Sublet, High Energy Weapons Archivehttp://nuclearweaponarchive.org/Nwfaq/Nfaq7-2.html#uk Lets call it about 4.5 tonnes of HEU was created by UK by the end of 1961, which at 50 kg per A-bomb equates to enough for about 130 to 140 implosive HEU weapon cores (or enough for use in about 80 much higher-yield thermonuclear bombs.This was achieved only 16 years from Hiroshima, by a country that was both devastated and basically in economic collapse and almost broke.The Russians also built the HEU JOE-1 very quickly because they could build the enrichment capability up quickly, and mine and enrich uranium quickly even with crude first-generation technology and zero experience doing it.And then there was the USA:"...The U.S. has produced no new nuclear warheads in the past ten years (the last fissile bomb core was fabricated in December 1989, the last weapon was assembled 31 July 1990). ... A total of 90.5 tonnes of weapon grade plutonium was produced by the U.S. 54.5 tonnes of this was produced at Hanford, 36 tonnes was produced at Savannah River. Three countries provided the bulk of the foreign-derived material: United Kingdom (5,384 kilograms), Canada (254.5 kg) and Taiwan (79.1 kg). ... On 1 March 1995, President Clinton declared 212.5 tonnes of highly enriched uranium (HEU) and plutonium to be excess to national security needs. Since that time additional information about the amount, locations, and forms of this material has been released. The excess plutonium (38.2 tonnes) is stored at 10 locations in Washington, Idaho, Colorado, New Mexico (two locations), Texas, Ohio, New York, Tennessee and South Carolina. The HEU (174.3 tonnes) is stored at six locations in Washington, Idaho, Colorado, New Mexico, Texas and South Carolina. It is expected that the HEU will be blended with natural uranium to produce some 7000 tonnes of civilian power plant fuel over 8-10 years. About 10 tonnes of HEU has already been placed under international safeguards at the Oak Ridge Y-12 site. The excess HEU consists of 33 tonnes of >92% enrichment material (originally used or intended for weapon primary cores), and 142 tonnes of 20-92% enrichment material (much of it used or intended for thermonuclear secondaries). No HEU for weapons use has been produced since 1964, and production of HEU for use in naval reactors ended in 1991 with future needs to be met from the stockpile. ... " - Carey Sublet, High Energy Weapons Archivehttp://nuclearweaponarchive.org/Nwfaq/Nfaq7-2.html#ukSo the US acquired a grand total of 90.5 tones of weapon-grade Plutonium during the cold war.The excess Plutonium was 38.2 tonnes, from the combined total of 212.5 tones of 'excess' weapon-grade materials, thus the amount of excess HEU in 1995 was then;212.5 - 38.2 = 173.4 tonnes of HEU deemed surplus to requirements (and all of it intended for use in nuclear weapon cores and tampers).So just this discarded HEU excess weapon-grade stock was 191.6% larger than the total peak stock of weapon-grade Plutonium that the USA ever acquired! And this is not even counting the large stockpile the US still retained for weapons and naval reactor uses, at that time, in 1995.And the key sentence is this; "No HEU for weapons use has been produced since 1964, ...", which means all of the many hundreds of tonnes of HEU was created before 1964! i.e. it was all enriched within just 19 years of Hiroshima's destruction. And once the USA had produced such a glut of weapon-grade HEU that it was pointless to make more, the US stopped enriching uranium above civilian reactor-grade from 1964.So creating HEU fast in huge amounts was not slow at all, it was instead extremely rapid, and done to global overkill levels in very short order.Australia had a secret uranium enrichment program operating from 1965 until about 1972; then another from about 1979 to 1986 (as South East Asia and Indonesia became very unstable in the mid and late 1970s which pushed Canberra into secret HEU enrichment again) then two further separate laser enrichment programs from 1986 (as we knew Pakistan, India and China were all building large arsenals). The ANSTO laser effort disbanded in 1994, and SILEX continued until about 1998. But more to the point; Iran has had the Pakistani (URENCO) enrichment technology available to it for over 20 years. It would be foolish in the extreme to assume they did not use it to secretly build up a national stock of weapon-grade HEU from a small hidden underground enrichment program, since about 1990, or soon after this. Iran was literally surrounded and being repeatedly threatened by nuclear powers the whole time. All that Iran is doing now is up-scaling the once secret underground effort and doing this more openly, because it can no longer be hidden, and also, it no longer NEEDS to be hidden. Iran is now in a position to withstand a military challenge or else test a weapon, if necessary, to prove a capability exists to an aggressor, and that it has existed for several years. So I reiterate, HEU is overwhelmingly the ideal path to secretly acquired weapon-grade fissile material. A large nuclear reactor complex is unnecessary to obtain nukes, and a reactor only becomes essential if a state wants to constantly replenished supply of tritium for a standing strategic-yield EMP capability.Weapon-grade plutonium is actually 100% unnecessary if the state decides it does not want to use it, or to deal with its numerous down-sides and complexities.So it would be a good idea to change policy and not continually antagonise and vilify Iran.
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