Iran’s Foreign Minister has admitted they cheated on the now defunct nuclear enrichment program. They violated the amount of low-enriched uranium-235, he says, as well as the rate of its production. In addition to non-compliance with caps on its stockpiles of low-enriched uranium: (660 lb); they also violated their stockpile limit of heavy water - set at 286 tons - and halting sales of surplus material overseas. The allowed U-235 enrichment level is 4%, enough to power a nuclear reactor but far below that needed for a weapon (80-90%).

Under the deal, approved by then-President Obama, limited inspection of Iran’s reactors, enrichment facilities and heavy-water production plants was allowed. But we now know, according to the Iranians themselves, that they have been violating the deal. Which means there is really no limit to what other dishonesty has been going on.

Consider the fact that Iran comprises a land area of 636,000 square miles, nearly equivalent to the state of Alaska. How much equipment and facilities could be hidden in such a vast and varied landscape? Iran is filled with mountain ranges, lakes and rivers, along with vast areas of farmland and timber. The Iranians have already shown that they can assemble vast complexes of state-of-the-art chemical and nuclear plants hidden out of sight of the world, and, of course, our inspectors. There is literally no way to prevent them from continuing their chicanery, nuclear agreement or not.

A typical nuclear power reactor can utilize fuel that is enriched to 3-4% U-235. Naturally-occurring uranium contains about 0.7% of the fissile 235 isotope; most of the remainder is the relatively stable U-238. To bring the U-235 to a level where it can be used in a power plant or weapon, enrichment is necessary. The most-used process is called “centrifugation.” It is straightforward but difficult and energy-intensive.

The centrifuge is a machine that operates on the same principle as a milk/cream separator. The material is spun inside the device with the heavier component (milk) moving to the outer walls, the lighter (cream) to the inside. This permits the separation of the two streams. With uranium the process is complicated by the fact that the two isotopes are nearly the same in atomic weight: 235 v. 238. To accomplish the separation, the uranium in its raw form, usually the oxide, is converted to the fluoride, the lightest molecular compound that can be made. That part is easy, but even as fluorides the molecular weights are nearly the same, meaning the densities of the streams are near identical.

Multiple stages are necessary even to reach the 3-4% level of U-235 permitted under the old treaty. To reach weapons levels of 90%, many more stages are needed, hundreds or thousands depending on the level.

The famous Stuxnet computer worm, developed by the Israelis with the help of the U.S., disabled Iran’s centrifuge program between the years 2000 and 2005 by hacking into their operating system. The Israelis apparently used a double agent to manually insert a thumb drive into the computer; the centrifuges literally spun themselves to ruin.

A common misconception deals with the minimum amount of U-235 needed for a weapon. This so-called critical mass is the amount of fuel needed to initiate and sustain a chain reaction. Simply put, the fuel in a nuclear bomb, U-235 atoms, explodes by absorbing neutrons, splitting into other atoms, and generating immense amounts of energy, consistent with the loss of mass. A chain reaction can only continue as long as the number of neutrons emitted in each fission, slightly more than two, is greater than those consumed and lost. Neutrons are lost as the fuel assembly expands in the intense heat. It is crucial, then, to enclose the reacting mass exposed to the emitted neutrons as tightly as possible. In practice, the uranium is wrapped in a blanket of beryllium. This metal, which is widely available, has the property of reflecting, rather than absorbing or transmitting the neutrons. It keeps them bouncing around inside the reacting mass, continuing the chain reaction. The whole process is begun by triggering an outer wrap of conventional explosive. An initiator within the fuel then starts the chain reaction.

The critical mass is often quoted as about 100 lbs. of 90%-enriched U-235. But this is only true for a non-enclosed device. In practice, the fuel would be compressed into a sphere, as described above. The actual critical mass for a working device is more like 12 lbs. for uranium fuel, and as little as 5 lbs. for plutonium. The heart of the weapon could be as small as a soccer ball. This, of course, comprises only a small part of the entire device; it does not include the electronics and materials of construction. Note that this eliminates the possibility of a suitcase bomb, often used in fictional TV and film dramatizations.

A plutonium bomb is within the means of a rogue nation like Iran. With plutonium as fuel, rather than uranium, the destructive capabilities of a bomb are magnified. Iran’s intentions in this direction are indicated by its production and storage of tons of heavy water, whose only use is in a reactor that produces plutonium from the U-238, which is in the fuel along with the U-235. The technology for the separation of the plutonium produced in such a reactor is well-known and available to Iran.

All this means that Iran could very likely be in business in just a few years. We know where much of the Iranian nuclear facilities are located; they could be destroyed if hostilities broke out. But, as mentioned earlier, other processing and assembly plants are probably already under construction at hidden sites.

As far as delivery of a nuclear weapon, the scenario is equally frightening. Iran already has an intermediate-range ballistic missile (IRBM) with a payload of 1000 lbs., able to reach Tel Aviv or any of several U.S. military bases.

In other words, we have much to fear from Iran in terms of nuclear warfare, in addition to other forms of terrorism. It is clear that the treaty that was just ended by our president was not in our best interest; in fact, the entire world was at risk. Iran is a rogue State, determined and increasingly able to cause terrible destruction. We are wise to give them the level of suspicion we should have given Hitler in the 1930’s.

On a personal note, I would like to be clear that I am not an avid fan of our current president. I find much of what he says and does harmful, distasteful and most likely illegal. However, the nuclear treaty approved by his predecessor was clearly a mistake. It needed to be ended.

Image credit: Pixabay

Jack Winnick is Professor Emeritus of Chemical Engineering at Georgia Tech. He has worked for NASA at the Johnson and Kennedy Space Centers and for the U.S. Nuclear Regulatory Commission at the Oak Ridge National Laboratory. He holds seven U.S. patents dealing with electrochemical separations and is the author of four novels based on the crisis in the Middle East.