Photo: iStock
The first stage of a hydrogen bomb cannot be scaled down, at least not easily. Photo: iStock

No matter what you think of the Singapore Summit – and opinion is deeply divided – one country was definitely missing and its absence is of deepest concern. That country is Iran.

There isn’t much point in denuclearizing North Korea if the end-result is that the technology, know-how and key personnel are shipped off to Tehran.

For years now, probably 20 or more, North Korea and Iran have been actively cooperating on both missiles and nuclear technology. Iran’s longest-range missile, the Shahab 3B, is based on North Korea’s  Nodong-1 series and has been much improved. The missile now has a new re-entry nose assembly and is capable of changing course to evade intercepts using rocket nozzle steering.

The missile can not only hit targets in most of the Middle East, it can strike as far as southern and eastern Europe, Russia and India. The Shahab 3B can carry a single warhead of 1 metric ton, or multiple warheads. With this size payload, the  Shahab is capable of carrying small nuclear weapons.

It should come as no surprise that North Korea had been testing small nuclear warheads, aside from the last blast, which may have been a plutonium-fueled nuclear test. The small-weapons tests look like enriched-uranium atomic bombs. From what has been observed about North Korean rocket tests, the biggest obstacle facing deployment of nuclear-capable missiles is a competent re-entry vehicle.

The Ryongchon disaster

Iran extensively cooperates with North Korea. Both countries built a Yongbyon-reactor clone in Syria, which was destroyed finally by Israel in 2007. Cooperation with Iranian and Syrian scientists became clear in the Ryongchon train disaster in 2004. While most now believe that the disaster was an accident triggered when trains containing incendiary materials collided, some harbor suspicions that the train was bombed using an explosive device tied to a mobile-phone trigger. Such a phone was found near the site and North Korea banned mobile phones for some five years after the explosion.

The intent of the alleged attack most likely was to kill Syrian (and likely Iranian) personnel who may have been shipped home on a Syrian military plane with the bodies of the Syrian scientists killed, who were probably heading into North Korea from China.

What changed the overall dimension of the train explosion was the fact that in addition to the scientists the train was carrying explosive materials, most likely ammonium nitrite, which is used as a fertilizer, as a replacement for TNT as a rocket fuel and for explosives. Ammonium nitrite was used in the Oklahoma City truck bomb that destroyed the entire front part of the multi-story Alfred P Murrah Federal Building.

In Ryongchon the blast not only destroyed the train but caused significant damage in the surrounding area, killing some 160 people and injuring 1,300. Most notably, the bodies of the Syrian scientists were shipped home in lead-lined coffins, suggesting the bodies were highly radioactive. If the reports are true, then along with explosives the train (or the scientists) were transporting a large amount of enriched uranium or plutonium.

If there was enriched uranium on board the Ryongchon train and proximate to the Syrian scientists on board, and since the train was coming from the Chinese border, it follows that the uranium was being brought by the scientists for use in tests carried out in North Korea.  Syria has neither uranium nor uranium-enrichment capabilities. Iran has set up centrifuge “farms” to enrich uranium.

Uranium vs plutonium

In early June, Iran signaled to the International Atomic Energy Agency that it intended to step up production of feed-stocks for its centrifuges, something it can do under the so-called nuclear deal, or Joint Comprehensive Plan of Action (JCPOA). The feed-stock for a centrifuge is uranium hexafluoride.

Yongbyon can produce plutonium (Pu-239) from uranium (U-238).  How much plutonium it can produce isn’t known, but until recently a plutonium-fueled bomb seemed out of reach for both Iran and North Korea. If this assessment is right, then the quickest way to get workable nuclear weapons is with a uranium bomb, similar to what was dropped on Hiroshima. The fact that all but the most recent North Korean blast were in that category means that what the North Koreans were doing is exploding uranium (atomic) bombs and that the fuel for them was likely coming from Iran.

As a historical footnote, the US had only one uranium bomb, which was never tested and was used against Hiroshima. The bomb dropped on Nagasaki was a plutonium device, and it had been tested. The US had other plutonium atomic weapons in its early arsenal before hydrogen bombs were developed. There was in 1944 and 1945 a major shortage of enriched uranium, which is why the plutonium bomb became the expedient way to get an atomic weapon. Iran, however, is in pursuit of both uranium and plutonium weapons.

As far as Syria, Iran and North Korea are concerned, they are partners.  The al-Kibar reactor destroyed by Israel was financed by Iran (an investment of at least US$1 billion).

There are a number of reasons to take the uranium route. Iran has the hardware to produce highly enriched uranium (typically 90-95% enriched U-235). It is far simpler to make a uranium than a plutonium bomb because a U-235-fueled bomb requires only a gun-type mechanism to set off an atomic blast, while a plutonium-fueled bomb requires a complex triggering mechanism and very high-precision assembly.

It would seem with the Singapore agreement that North Korea could turn around the deal with Iran and ship its technology to Iran along with its scientists. The ballistic missiles that hit Saudi Arabia fired from Yemen allegedly by the Houthis (but probably by the Iranians) are full of electronics and other components manufactured in Iran. The alleged Houthi missiles were shipped in sections to Yemen and welded together in the field, probably to conceal the transshipments from satellite observation.

What this means is that North Korea could continue its nuclear development and work on improving its missile technology situated in Iran. At any moment in the future, North Korea could bring home its nuclear weapons and even its missiles and re-emerge as a significant nuclear power. Likewise, it means that Iran can do the same thing.

Consequently, the Singapore deal must include prohibitions on North Korean cooperation with Iran or with any other dangerous state, such as Syria or even Iraq or Lebanon, especially if Iran gains significant political and military control of these countries (which already seems to be the case in Syria and Lebanon).

The US must consider pushing the Iranians out of Syria, Iraq and Lebanon as urgently as it can, and it needs to get ironclad assurances that North Korea will stop all missile and nuclear cooperation with Iran or its partners.

Stephen Bryen

Dr Stephen Bryen has 50 years of leadership in government and industry. He has served as a senior staff director of the US Senate Foreign Relations Committee, as the deputy under secretary of defense for trade security policy, as the founder and first director of the Defense Technology Security Administration, as the president of Delta Tech Inc, as the president of Finmeccanica North America, and as a commissioner of the US China Security Review Commission. Dr. Bryen is a senior fellow at the Yorktown...