Transcript for How will Trump and Kim's meeting affect negotiations going forward?

President trump and North Korea's Kim Jung on behind closed doors now in Hanoi after a quick stroll through a lush garden poolside. They met when aids they shook hands. Aides are mark how hot it was in about the French architecture in Vietnam but they are getting down. To serious business and ABC's Devin Dwyer is where this. From Washington DeVon. Hey Aaron thanks so much and I'm here with Richard Johnson senior director of the nuclear threat initiative here in Washington the former State Department official. Who was involved in North Korean nuclear negotiations in the past and packed way into the country. To inspect some of their nuclear sites just over ten years ago Richard great to have you were also senior advisor on Iran nuclear DOC you know. This nuclear stuff. Ask you at this juncture as we watch these pictures. And listened to president Franck talk very optimistically about another deal it seems like we've been here before him. In fact many of the same things are on the table again. How is this moment is this moment in different. Well I think it's different in a couple of ways I think first of all we are now doing something at the leader level so in the past negotiations. This has always done at the working mobile ambassador. Somebody maybe the secretary of state like Madeleine Albright who went to North Korea. But we never had a president actually meet with the leader of North Korea some people criticize that is giving too much credence to Kim Jong-un. But it's a top down system and so I think it makes sense to start at the top so that's a big difference now you're right that we've been here before we talk a lot about young beyond. And this facility where they haven't reactor where they have a re processing plant where they can pull out the plutonium that's our biggest nuclear development that's right on BO that's right that's where most of their locations probably are and this enrichment plant that was revealed back in 2010. Which by the way when I went to young beyond I was in that building but it wasn't an enrichment plant yet so they were developing things. Clandestinely which makes people concerned. Asked about young beyond its nuclear site North Korea it gets so much attention it is. It's a location that in previous negotiations back in the nineties. The leaders of North Korea agreed to dismantle agreed to shut down we heard coming into this talk with president from that perhaps Kim Jong-un. Could offer that up again you know. Should that be greeted with significant skepticism and how hard would it be to shut down a restart you've been. Well here's where terminology becomes very important and where I've been saying that one of the things that we need. It's not just to have these leader level summits but working level summit for you have technical negotiators. Parking every word because there's a difference between dismantling. Which is really and you program. And disabling which is what was happening in the six party talks and when I was there I was looking at. Things that happened that were. Reversible and in fact they did reverse it and within a couple of months a couple of within a year they were back up and running so I think we need to look at the term that they use. And I think we need to look at verification. We want the international atomic energy agency hopefully this is the international regime that oversees these things. To be in there to see what they're doing and whether it's significant that at the end of the day. Even if it's just a temporary shutdown. Capping their program and stopping production of highly enriched uranium and plutonium which is what fuels their bombs would be a very good thing. One of the things that was so critical to the work you did Richard Richard Johnson senior director at the nuclear threat initiative in your negotiations with both North Korea in the past. In Iran more recently was to demand an accounting from those governments of all their weapons that you can go in and verify the drug administration said going into this summit. That they aren't even asking for that at this point they want it ultimately but at this point they simply want a roadmap. And the administration's term is what do you make of that. So I've been a big advocate for getting a declaration upfront but I've also said in the same breath any declaration you're gonna get is going to be incomplete and incorrect. That shouldn't be a red flag for us it should be a sign of the start of a process some people would say if they don't admit everything ala once. Then they're taking us for a ride I don't agree with that and there was a story even today claiming that the administration has backed off and that this was that they concession. Actually think that if the administration's position is we're going to do this step by step starting would young beyond. And then bill that declaration out that would actually be a realistic way of doing this and it gives us the ability to go and ask for more information. Richard Johnson senior director of the nuclear threat initiative with us former State Department official involved in North Korea negotiations the Iran nuclear deal as well Richard before we let you go. Your organization now the nuclear threat initiative studies North Korea has one of the best databases of the very tough to get intelligence about what's in the what do we know about of the arsenal that Kim Jung Hoon has right now what's the best estimate that. Well there's lots of wide ranging estimates and a lot of this comes down to whether or not North Korea has facilities that it has not declared particularly uranium enrichment and that's a big open question. Right now there's ranges between twenty to sixty nuclear weapons as Sig hecker at Stanford recently said it's probably between 35 and 37. But they also have a lot of nuclear capable missiles that they tested. Including ICBM is now the interesting factor there is is that we don't know whether their ICBM can actually deliver. A nuclear weapon because they've never tested the so called re entry vehicle that would have to survive the atmosphere reentry. To actually land in investing. Pretty close they were getting closer that's where this idea of a missile freeze is a good thing but when the president says that he's in no rush I hope looking means is not that there's not urgency. I hope what he means is that that we can take some time to do this the right way but we certainly need to get at it. Beginning now Richard Johnson fascinating perspective senior director of the nuclear threat initiative former State Department official nuclear. Inspectors inside North Korea agreed to have you with us Richard think he's so much here actors in New York back to you.

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