RENEE MONTAGNE, HOST:
We may get an historic meeting between President Trump and North Korean leader Kim Jong Un - or maybe not. This past week, Trump accepted an invitation to meet with the North Korean head of state over giving up its nuclear weapons. But then a day later, the White House appeared to add a precondition. The summit would only happen if North Korea took, quote, "concrete, verifiable action." For its part, North Korea has said it is willing to pause further nuclear and ballistic missile testing while talks are underway. For more, we reached Sig Hecker via Skype. He's a former director of the Los Alamos National Laboratory. He first visited North Korea's nuclear facilities in 2004 in an unofficial capacity and came and went half a dozen more times in the next few years. Welcome.
SIEGFRIED HECKER: Thank you very much, Renee. It's my pleasure.
MONTAGNE: And, you know, last year, we saw North Korea launch almost two dozen missiles, including its first intercontinental ballistic missile. In that context, how meaningful would a pause, which is spoke about - a pause in missile testing be?
HECKER: Both a pause in missile testing and a pause in nuclear testing is still very significant. Yes, they did indeed test two different intercontinental ballistic missiles, particularly one very big one, which was an impressive feat. But it takes more than one test to have a ballistic missile fleet. So stopping the missile testing is still significant.
MONTAGNE: But let's take a step back here then. You've been to North Korea seven times - to their labs. How would you describe its nuclear capabilities?
HECKER: So they're very competent, very professional and, quite frankly, surprisingly good. You know, we've had a tendency in this country to sort of dismiss North Korea as a backward country. But it's not. In the nuclear arena, there are two paths to the bomb. One is the plutonium path. They showed me all of that in 2004 - not very fancy but good enough. And then in 2010, they actually showed me centrifuge facility. That was simply astounding. It was a modern facility, and it was remarkable for them to have that.
MONTAGNE: One of the goals of these potential talks is the denuclearization of North Korea. Given they've got such capabilities, how likely is it to happen?
HECKER: Well, first of all, I think it's not very likely to happen. What's significant in the current situation is they've actually said that they would be willing to give up nuclear weapons, you know, if their security is assured, and they're not threatened. However, to think that's going to happen in the short term is just not realistic because to build a nuclear weapons program, it's an enormous number of facilities. It's a large number of people. It took, well, more or less 50 years but particularly the last 25 years to get to where they are today. They're not going to turn that over overnight.
MONTAGNE: Well, short of full denuclearization, what other steps could North Korea take to prove, you know, its sincerity in this?
HECKER: So there are very important steps. And one can lay those out. In other words, I look at the things that are highest risk. And those are the things you want them to stop first. So two that were highest on my list - they have, for the time being, said they would do a moratorium. And that's no more missile tests and no more nuclear tests - because to increase the sophistication of your bombs, you have to do more nuclear tests. The next one would be not to make any more bomb-grade material, which means stop the operation of the reactors. All three of those are verifiable. The problem is on the bomb-grade material, you can also go the uranium route. Those are the centrifuge halls. We know where one of them is. We don't know where the other one or two are. And that will be extremely difficult to verify. And that's going to take a long time and a real detailed process with them to get there.
MONTAGNE: From what you know of North Korea from your time on the ground, are they motivated to use these weapons? Is this something to really be afraid of?
HECKER: What I worry about when it comes to the weapons is - one is capability. Second is motivation. And capability - for many years, I was able to say, look. You know, they have the bomb, but they don't have much. They don't have a nuclear arsenal. Then comes the motivation part. And would they be motivated to go ahead and attack the United States, Japan or South Korea basically out of the blue? I say absolutely not. They want those weapons to make sure to protect them. Perhaps they want the weapons so that they actually have sort of sufficient maneuvering room, you know, on the Korean Peninsula. What I've worried about is not so much that they're motivated to attack us but rather that we're going to stumble into a nuclear war.
MONTAGNE: Sig Hecker is a former director of the Los Alamos National Laboratory, now at the Center for International Security and Cooperation at Stanford University. Thank you very much.
HECKER: My pleasure. Transcript provided by NPR, Copyright NPR.