Thae Yong-ho, the former North Korean deputy ambassador to the UK, defected to South Korea with his family in 2016. He remains the highest-ranking diplomat ever to defect from North Korea.

In an interview with 101 East reporter Mary Ann Jolley in Seoul, he gives rare insights into the inner workings of the Kim Jong-un regime. Thae believes that a people's revolution will one day bring an end to the Kim family's dynastic rule.

The family members of defectors are often targeted by the North Korean regime.

Thae reveals that he does not know the fate of his siblings. "Even though I am physically and mentally free in South Korea, I still can't get rid of this nightmare of my family members," he says.

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Al Jazeera: You've been a diplomat for many years. You've been loyal to the North Korean regime. What made you decide to defect?

Thae Yong-ho: There are a couple of reasons for my defection. First of all, it took me quite a long time to prepare this defection because it was quite a long time since I didn't believe in this regime. And I did think that there was no hope for this regime, but in order to make the final decision, for making this kind of defection, it was not so easy, the decision. So it's a little bit hard to say what is the triggering point.

Al Jazeera: When did you start to have doubts about the regime, was it after Kim Jong-un became the leader or had it begun before then?

Thae: Actually, you know, there was basic suspicion and doubt about the North Korean system and regime, but that kind of doubt did not lead me directly to the defection. But my frustration about the North Korean regime and the society actually started when Kim Jong-un decided to choose to continue the policy line of his grandfather, Kim Il-sung and his father Kim Jong-il.

Kim Jong-nam was a great psychological burden for Kim Jong-un to legitimise the leadership as the only successor of his father. Thae Yong-ho, North Korean defector

Actually, when Kim Jong-un first came to power, I was hopeful that he may bring some change and organisation to North Korean society since he studied a long time abroad, he knew the world, so I was fairly hopeful. But later, Kim Jong-un decided to choose the continuation of the policy rather than bringing any change to North Korean society.

Especially in March 2013, he decided to openly continue the development of the nuclear programme of North Korea, that was his actual announcement of his decision to continue the policy line of his father and grandfather. And several months later, after this official announcement in December 2013, he executed his uncle and the people around him who actually yearned for change in North Korean society.

So, Kim Jong-un started not only to continue the main policy line he also started to purge and execute the people who actually longed for change in this society. So, this kind of development pushed me further to finalise my conclusion of defection.

Al Jazeera: What was your greatest concern about defecting?

Thae: There are also family reasons. I am the father of two children and I am really worried about their future because I lived in that system for more than 50 years and I can very easily imagine what kind of life my sons would lead.

To be honest, my life in North Korea was nothing but the life of the slave, so I really didn't want to hand over the same destiny and the life which I led to my sons' generation. So, I really wanted to give them freedom. I just wanted to see my sons lead a normal life like other people.

Al Jazeera: What about your family in North Korea?

Thae: In North Korea, defection itself is really a great offence to the system and to the leadership. The families associated with defectors would be heavily punished, especially the families of higher-level defectors like me. So, of course, so far I'm not well-aware of the actual whereabouts of my family members and my brother and sister, but so far what I have seen about those happenings with my colleagues who defected in the past, I'm sure that my families could face a very heavy punishment because of me.

Al Jazeera: And that's a heavy burden to carry ...

Thae: Of course, even though I am physically and mentally free in South Korea, I still can't get rid of this kind of nightmare of my family members.

Al Jazeera: Did you ever meet Kim Jong-nam?

Thae: I met him a couple of times in the late 1990s at the entrance of Koryo Hotel in Pyongyang, but I didn't meet him face to face. What I learned was that he loved to be, and mix with, even, some of the foreigners who were staying at the hotel.

Al Jazeera: What was your reaction when you heard Kim Jong-nam had been murdered?

Thae: On that morning, when I switched on the TV, the world media all of a sudden burst into breaking news, but to me it was not such a kind of surprise because according to Kim Jong-un or the North Korean regime, Kim Jong-nam was a kind of physical hurdle which should be eliminated ... sooner or later.

Al Jazeera: Who do you believe killed him?

Thae: I think, in North Korean society, it is quite obvious that this kind of big incident can only be ordered by Kim Jong-un himself ... Some media reported that maybe this is the outcome of a kind of royalty contest or competition. Kim Jong-nam is the half-brother of Kim Jong-un and nobody in our system can ever suggest to kill the half-brother of Kim Jong-un. So, this is a very obvious fact, that it is Kim Jong-un's decision.

Al Jazeera: Why did Kim Jong-un want him dead?

Thae: North Korean society, like in South Korea, has a very Confucian influence on society where the people should obey the instructions of the leader, children should respect their parents, and little brother should respect the elder brother. So, this is the long-term tradition and ... Kim Jong-il made an official party policy line ... the branches of a tree should be cut off in order to let the main trunk of the tree grow well. That is the main official terminology of the North Korean Workers party.

In other words, the first son of the family should inherit the family business. That is the usual practice, no matter whether in the North or South. So, Kim Jong-il was successful in being appointed as the heir to Kim Il-sung because of this party policy, because he was the first son. But if Kim Jong-un followed this policy, it is Kim Jong-un who should be eliminated because he is actually the branch of the tree, rather than the main trunk. It is Kim Jong-nam who is the first son ...

Kim Jong-nam was a great psychological burden for Kim Jong-un to legitimise the leadership as the only successor of his father.

Al Jazeera: Kim Jong-nam made it clear that he didn't want to be involved in politics. Why then was he a threat to Kim Jong-un?

Thae: Kim Jong-un has been in power for five years, but until now he has been in difficulty legitimising his leadership. For instance, Kim Jong-un still hasn't presented his age, his place of birth, where he spent his childhood, what's the name of his mother. So, everything is in ambiguity in North Korean society about Kim Jong-un ... He finds it difficult to convince the society and North Korea, most of the people even don't know anything about the existence of Kim Jong-nam, the first son of Kim Jong-il, because his mother was not the official wife of Kim Jong-il. And the mother of Kim Jong-un was also not the official wife of Kim Jong-il. So these sons are not official offspring of the official wife of Kim Jong-il, so it's a very great burden for the legitimacy.

And Kim Jong-nam, during his stay abroad, from time to time, met foreign media and so Kim Jong-un was very afraid of a spread of this kind of news of his existence from outside. So, I think it was a standing order for Kim Jong-un to get rid of Kim Jong-nam any time.

Al Jazeera: What do you make of the use of VX to kill Kim Jong-nam?

Thae: I think the North Korean agents thought that the Malaysian authority could not find the chemical component of the medicine they would use ... Kim Jong-nam felt something strange, that's why he approached the airport security police and explained what happened to his eyes and it was very fortunate that CCTV at the airport caught all these things.

So, the investigations were able to focus on his face and what chemicals, but otherwise if Kim Jong-nam just naturally continued his journey and fell down on his way to the airplane, it could be very difficult for the world and Malaysian authorities to find out what caused his death.

Al Jazeera: How has the use of a chemical weapon escalated the threat of North Korea to the rest of the world?

Thae: It is not a hidden story that North Korea has been stockpiling huge amounts of chemical weapons. Actually, chemical weapons are the weapons of the poor countries. Any pharmaceutical or fertiliser factories can produce very sophisticated chemical weapons. So, North Korea has been producing the chemical weapons for quite a long time.

Al Jazeera: Do you think the fact that they've now used it on foreign soil to kill somebody suggests that they may not fear using it?

Thae: Of course, the Kim Jong-un regime is not only developing the nuclear weapons, actually it is ready to use them in this 21st century. So Kim Jong-un may not hesitate to use any weapons if he feels threatened.

Al Jazeera: He's executed family members, key members of the regime and now he's murdered his own brother. What does that tell us about the brutality and cruelty of his regime in comparison to that of his father's and grandfather's?

Thae: Yes, the persecution and purge was also a frequent thing in North Korean society, even during the Kim Il-sung and Kim Jong-il period. But Kim Il-sung and Kim Jong-il never executed their family members. Kim Jong-un is different, because he doesn't have any sense of solidarity among the family members and even the relatives because Kim Jong-un was a hidden boy. Not only in North Korean society, but he was also a hidden boy to the family members of his father and his grandfather.

The Kim Jong-un regime is not only developing the nuclear weapons, actually it is ready to use them in this 21st century. Thae Yong-ho

Even up to now, Kim Jong-un cannot present a single photo with his grandfather because his grandfather, Kim Il-sung, didn't know the existence of this grandson, Kim Jong-un. So, he doesn't have any sense of solidarity with the rest of the family.

And to my impression, Kim Jong-un is in great fear of those officials around him because those officials are old and the ones who used to be followers of his grandfather and his father. Kim Jong-un is always sensitive whether he's looked down upon by them as a young leader or whatever, so Kim Jong-un is a man with great paranoia.

I think on the surface, Kim Jong-un's system looks very formidable, but I think Kim Jong-un's system has already been in a slippery slope towards collapse. So, the only thing Kim Jong-un now relies on is the reign of terror. He just continues to execute officials.

For instance, a few months ago, he even purged the high-ranking officials of his security service network. So, if the system even purges officials of this secret, the security service, then it proves that the system is in crisis.

Al Jazeera: What about the ordinary people? Has their life changed under Kim Jong-un?

Thae: The North Korean people these days are in great fear because Kim Jong-un even killed his uncle, and when he killed his uncle he made this execution open and public, so people saw enough. So, when people learnt that Kim Jong-un even went as far as to kill his uncle, then that means that he could kill anyone. So people are in great fear, that's the first thing. The second thing is that the North Korean people have been living in these kind of circumstances and environment for a long time. So, to some extent, they are indifferent to what's going at a higher level of the society. They are just taking care of their own daily survival rather than thinking something big.

Al Jazeera: What could stop the North Korean regime to develop nuclear weapons?

Thae: I think the only way to solve the nuclear threat is the final elimination of Kim Jong-un and the regime. I think in order to eliminate Kim Jong-un's regime, there can be several options even including the military ones, but the most realistic and effective is to disseminate the outside information in order to educate North Korean people for a popular uprising against the regime.

Al Jazeera: Do you think this is possible?

To my interpretation there is a real huge people's resistance to the system even in North Korea especially in the economic field. Now in North Korea, the daily life of survival is highly dependent on the general market. so it is the capitalist market system which is providing for the survival of North Korean people, not the socialist system of the government. And the more this kind of capitalist element is growing, the more independent way of thinking and also the people's yearning for their own rights will grow and expand. And one day I think the people's awareness of this kind of right for survival could evolve to a kind of right for political freedom.

In North Korea these days, the people in the elite group and also people in the security and enforcement network, they also share the same, the sense that there is no hope for this system. So once there's any kind of spark of people's uprising, I think these huge networks can do nothing.

Source: Al Jazeera News