how nuclear inspectors can inspect other countries nuclear weapon inventories and uranium refining abilities in a way that can be trusted and not just staged by the inspected country

Question

how nuclear inspectors can inspect other countries nuclear weapon inventories and uranium refining abilities in a way that can be trusted and not just staged by the inspected country

In: 1404

Answer 1

Due to the rarity of plutonium, initially you pretty much have to start with uranium if you wish to build a nuclear weapons program. So, let’s start with uranium.

Uranium just taken out of the ground cannot be used for bombs or fuel. This uranium contains only about 0.7 percent U-235, the type of uranium that can sustain a nuclear reaction. For actual use as fuel you need something like 3 – 5%, and for use in nuclear weapons you need something like 20%.

It is necessary to process the uranium to make the type of uranium needed for either one in large centrifuges. Such a facility is very hard to hide, so if someone wants to process uranium in this fashion they will likely have to explain the processing plant as a plant for producing nuclear fuel for reactors and allow inspection.

A single pass through a centrifuge does not do the job. You have to have the output of one centrifuge fed into another in a chain until the end product has a high enough percentage of U-235 for your purpose.

Since fuel needs a lot less refining than bomb material, the bomb material chains of centrifuges are much longer than ones used for fuel. Given the size of the centrifuges, the difficulty in moving them about and reconnecting them, and being able to cover up the fact that you did this, all in a short period of time after you are told that an inspection is coming, it is effectively impossible to hide a nuclear weapons uranium purification plant by disguising it as a nuclear fuel plant.

Similar issues occur if you try to build a breeder reactor to make plutonium. You can’t just rebuild the reactor every time the inspectors show up, and so you cannot hide the fact that your reactor is producing plutonium. Since nearly the only use for even moderate amounts of plutonium is nuclear weapons, again, you are given away.

Minor edit: 20% is reported to be the minimum needed for weapons development, which I believe means used to create plutonium. It is at or just under 90% if you wish to use straight uranium. However, a straight uranium bomb is larger and harder to deliver than a plutonium one, and as much more likely to be used in creating a weapon