Prepare for all manner of frothing at the mouth from wingnuts about Iran’s “industrial scale” enrichment program.
Just as a quick primer: like many elements, there are multiple types – isotopes – of uranium. From a chemistry perspective, they all behave identically. However, they weigh slightly different amounts, and of the two that occur naturally (uranium-235 and uranium-238) only the less common uranium-235 can be used directly in a nuclear weapon (uranium-238 can be made into plutonium in a nuclear reactor, though). Enrichment is the process of separating out the uranium-235 for one of two purposes – to make a mix of roughly 5% U-235 and 95% U-238 for use in a nuclear power reactor, or a mix of roughly 90% U-235 and 10% U-238 to make a nuclear bomb. Depending on the sophistication of the design, somewhere between 20 and 60 kilograms of this mix would be required for a bomb.
Because they behave essentially identically in chemical reactions, the main way to separate them is to take advantage of the slight difference in mass, and the standard method of doing so is to atomise the stuff (by making it into a gas) and spinning it in a centrifuge, a little like panning for gold. Iran has been trying to master this very difficult task for some time now, and the guts of their current announcement is that they now have 1,000 of their centrifuge designs going at once, and plan to go to 2 or 3000 soon.
So does this mean that Iran will be making nuclear weapons any time soon?
Not according to Jeffrey Lewis. His latest post on Iran explains the severe limitations of Iran’s uranium program. The short version – because of various technical problems, Iran doesn’t seem to be able to keep its centrifuges running for more than 20% of the time, it’s not clear that they can actually mass-produce the centrifuges at all (which they would need to to actually produce enough material for even a minimal arsenal), and they don’t seem to be able to produce pure enough feedstock to actually feed into the centrifuges. These things spin so fast that if the stuff you feed in isn’t very pure, the centrifuge will break into a million pieces.
Short version? While the Iranians are undoubtedly seeking a nuclear weapon – or at least the option of building one at short notice (their enrichment plans make no sense whatsoever as a commercial enterprise) – everything we know suggests that they still a long, long way from either. Even if you buy the premise that imminent possession of a nuclear weapon by Iran justifies military action (I don’t), that point will not be reached until well after January 2009.