North Korea likely to test a second-stage hydrogen bomb

North Korea has been working on developing a second-stage hydrogen bomb that is smaller in size and uses less weapon-grade uranium.

In an interview, David Albright, a prominent US nuclear scientist, and director of the US Institute for Science and International Security (ISIS), said that North Korea’s hydrogen bomb has not progressed significantly and that the country is rushing to conduct its seventh nuclear test because more steps must be taken in the future to complete it.

North Korea is accelerating the rebuilding of the Punggye-ri nuclear test site, according to reports. According to one theory, the work is being done in preparation for the 7th nuclear test to resume. What information do you have concerning North Korea’s nuclear test preparations?

[David Albright] North Korea appears to be on track to restart nuclear testing in the coming months if it so desires. However, nothing is known about the tunnels that North Korea is rumored to be recovering. We don’t even know how deep the tunnel is, for example. There is still a lot of uncertainty, and forecasting is tough. If the installation of cables in the tunnel is observed, it indicates that a nuclear test is planned. Several pieces of equipment must be brought into the tunnel, wires must be connected, and explosion data must be recorded, but I don’t believe that has been confirmed yet. Of course, I might be wrong, but I believe we should be cautious in forecasting a nuclear test in the next weeks. It’s seldom easy to determine exactly what’s going on.

If North Korea’s nuclear test preparations are real, why is it in such a rush to resume the test? What type of target do you think you’re looking at?

[David Albright] It’s difficult to say, but I believe North Korea is interested in thermonuclear weapons. As a result, it is likely that a nuclear test will be conducted in connection with this. Meanwhile, North Korea has successfully tested fission bombs with a strength of 10 kt and 20 kt, as well as technology connected to them. We’ll perform more studies and do more trials in the future, but I believe the hydrogen bomb is the most serious issue. Stage 1 hydrogen bombs are massive and inefficient, needing 50 kg of weapon-grade uranium apiece. North Korea, in my perspective, intends to construct a second-stage hydrogen bomb, and it must go through a number of steps to get there. We also need to dig further into the tunnel to avoid spilling dangerous radioactive material from a nuclear test, and we can dig deeper until we’re sure there won’t be any radiation exposure.

North Korea is thought to have between 20 and 60 nuclear bombs. Of course, the sort of nuclear bomb makes a difference. How many do you think there are now?

[David Albright] Over the next several months, our lab is also attempting to re-estimate the number of nuclear weapons in North Korea. I’ll also do research dependent on the weapon kind. So far, I’ve said that North Korea has between 20 and 60 nuclear bombs. It’s pretty much the same as before. Even this figure is questionable, as it depends on how much weapon-grade uranium is used in nuclear weapons, as well as the type and number of hydrogen bombs North Korea desires. For example, a stage 1 hydrogen bomb requires 50 to 100 kg of weapon-grade uranium, but a stage 2 hydrogen bomb only requires 15 to 30 kg. That is why North Korea is attempting a hydrogen bomb test.

So, how far do you believe North Korea’s hydrogen bomb has progressed?

[David Albright] I don’t think we’ve made much progress yet. One nuclear test is insufficient. I believe it is still in the early stages of development. North Korea may have gotten assistance in designing the bomb from China, Pakistan, and other countries, but I believe it requires additional testing since there are numerous technical details that need to be addressed. As a result, I believe that the majority of North Korea’s weapons are fission weapons, which they have been testing for several years in order to improve their capabilities. The power is predicted to be between 30 and 50 kt.

How would you grade North Korea’s nuclear warhead downsizing and re-entry technology, both of which are critical nuclear weapons technologies?

[David Albright] I believe North Korea would have made significant advances in re-entry technology if it had collaborated with Iran. Iran has a number of missile projects, and Iran and North Korea have exchanged knowledge on reentry technology. So, I believe North Korea is aware of re-entry technology, although it is not yet mastered. The re-entry technology for medium-range ballistic missiles does not appear to be complex (as opposed to intercontinental ballistic missile technology), hence it appears to be well-known. The issue is that it is not evaluated for reentrant abilities. As a result, a collaboration between North Korea and Iran is becoming increasingly vital. North Korea may have requested Iran to research re-entry technology, or it may have inked a deal. This is because, from the late 1990s to the early 2000s, Iran was actively studying reentrant technology.

In a situation where North Korea has already launched an intercontinental ballistic missile and the risk of a nuclear test is increasing, what do you view as the most concerning variable in the North Korean nuclear threat moving forward?

[David Albright] It’s a hydrogen-bomb-related nuclear test. It’s actually a test of a hydrogen bomb’s fusion detonation. This nuclear test by North Korea would be the worst since it would be far more catastrophic. With its last missile test, North Korea has heightened international tensions; but, if it performs a nuclear test, the world community will be even more concerned, and if it is a hydrogen bomb, it will be even more startling.

In this context, the Biden administration’s North Korea approach appears to be quite similar to the previous strategy of strategic patience. What recommendations do you have for South Korea and US strategy toward North Korea?

[David Albright] Whether or if denuclearization is achieved, I endorse the policy. Even if North Korea does not accomplish denuclearization in the short to medium term, it is critical that it does not replicate Pakistan’s and India’s errors in becoming nuclear powers. After testing nuclear weapons, both nations became nuclear-weapon states, and it is critical to learn from this experience and sustain a policy of sanctions in order to achieve North Korea’s disarmament. One of the things I believe the Biden administration should do is strengthen sanctions against North Korea and put secondary sanctions on China. Because China is assisting North Korea in acquiring weapons of mass destruction and other sanctioned products, secondary measures are required. I recommend that we talk with North Korea after first exerting pressure on it. Because North Korea is now unwilling to negotiate with the United States, it is vital to sustain pressure on China and persuade it to behave responsibly through secondary sanctions.

Some even argue that disarmament is impossible due to North Korea’s superior nuclear and missile capabilities. Do you believe North Korea can still achieve nuclear disarmament?

[David Albright] Maintaining the aim of denuclearization is critical, in my opinion. When talking about denuclearization, though, it’s important to know what type of nuclear weapons North Korea has. We don’t know anything about North Korea’s nuclear program since it hasn’t done even the most basic of verification. For example, I departed when former President Donald Trump didn’t receive what he wanted at the Hanoi meeting. I considered myself fortunate. Because North Korea is producing three times as much nuclear material in secret locations as Yongbyon. As a result, estimating the size of North Korea’s nuclear program, including nuclear facilities and materials, is challenging.