Note: This interview by  Changsop Pyon originally appeared in Korean at SisaIN.

SisaIN: You suggested that the best way for denuclearization is to convert N. Korea's nuclear and missile programs for civilian use rather than total denuclearization. Is it because 'total denuclearization' or 'complete denuclearization' as agreed between Trump and Kim Jung Un is impossible to achieve under any circumstances?

Hecker: Total or complete denuclearization will be difficult to achieve because North Korea will likely insist on retaining a peaceful nuclear program (such as nuclear medicine and nuclear electricity) and peaceful space program to launch satellites. Elimination of the military programs may be possible, but it will require a phased approach that will take years. In addition, verification of the elimination of the military programs will be almost impossible unless North Korea is prepared to cooperate.

SisaIN: You suggested a 10-year road map on denuclerization marked by “halt, roll back and eliminate’ North Korea’s nuclear and missile programs.  Assuming this process would be going on, what would be the incentives or compensations for the US to give to North Korea? Completion of peace treaty and normalization, in addition to economic assistance and sanctions relief during the 10-year time frame?

Hecker: An agreement with Pyongyang should be structured to achieve denuclearization and normalization. It should be agreed in the beginning that denuclearization would occur in phases to halt, roll back and eventually eliminate the nuclear weapons and nuclear weapons program. As we indicated in our ten-year roadmap, that will take time. Our proposed approach of conversion from military to civilian nuclear programs constitutes an important step toward normalization. Additional steps toward normalization, such as some sanctions relief, potential assistance with energy supply, and an end-of-war declaration will have to be phased with Pyongyang taking significant steps to roll back its weapons program.

SisaIN: The Trump administration is putting a high priority on verification of N. Korea’s nuclear weapons and programs under the banner of ‘FFVD (final, fully verified denuclearization). You introduced the new concept of 'cooperative conversion' for the best chance of the verifiable denuclearization of N. Korea's nuclear programs. 'Cooperative' in the sense that S. Koreans and Americans are working together with their N. Korean scientists and engineers to eliminate the nuclear weapons. Is this 'cooperative conversion' possible without them building mutual trust first?

Hecker: We believe that ‘cooperative conversion’ will allow the two sides to build trust. In other words, it would be the nuclear program that would now catalyze building trust, whereas in the past it has been the greatest source of conflict. With American and South Korean technical personnel on the ground working closely with North Korean nuclear experts to advance civilian programs, they will be able to learn much more about the nature and extent of the North’s entire program and see facilities that might otherwise escape them.

SisaIN: Can any agreement to eliminate nuclear weapons without cooperation be verified?

Hecker: Without cooperation, we also see no way that the elimination of all nuclear weapons and weapons programs can be verified. The magnitude of the North’s nuclear and missile programs and the closed nature of the country will make verification of complete denuclearization virtually impossible. It will not be possible for inspectors, especially in an adversarial environment, to get unfettered access to all of North Korea’s facilities to verify that it has not secretly kept a few nuclear weapons, a few kilograms of plutonium, or one or more covert uranium centrifuge facilities. But cooperation on converting Pyongyang’s nuclear infrastructure will help.

SisaIN: As you admitted, this civilian nuclear and space programs would be highly controversial in the US because of North Korea's possible retention of nuclear capability. The United States had the bitter experience with this back in 2002, when James Kelley confronted the North with the evidence of its secret nuclear program in violation of 1994 Agreed Framework. So, how can the US make sure the North would not make the same mistake again?

Hecker: We believe the situation in October 2002 was more complex than just stating that North Korea cheated. It is true that the North was covertly pursuing uranium enrichment while freezing the plutonium complex in Yongbyon. However, Pyongyang can also accuse Washington of not keeping its Agreed Framework and October 2000 Joint U.S.-North Korea Communiqué commitments to normalize relations. Although there were some difficult times during the Clinton administration years of the Agreed Framework, these difficulties were resolved by the end of 2000. However, the Bush administration was determined to end the Agreed Framework in 2001 and 2002. Adding North Korea to the Axis of Evil, for example, was certainly not in keeping with the U.S. government’s commitment to normalize relations. Consequently, it is no surprise that Pyongyang views Washington’s promises to normalize as insincere as Washington views Pyongyang’s promises to denuclearize.

Military to civilian conversion actions will certainly have to be monitored by international inspections. Converting programs and facilities cooperatively will also give U.S. and South Koreans much better access to allow more complete verification. Moreover, we believe that it is important that the conversion activities be allowed to proceed sufficiently far that Pyongyang would have too much to lose should it back out of its agreement. In other words, the more North Korea would benefit from nuclear conversion and from other normalization actions, the greater a price it would have to pay to break out. Consequently, the more reason it will have to keep agreements.

SisaIN: Regarding N. Korea's retention of its nuclear capability, there is the issue of what to do with their thousands of nuclear scientists and engineers among other things. As long as they are physically inside North Korea, can the Kim Jung Un regime use them anytime to restart their nuclear programs?

Hecker: Civilian conversion would help to take care of this problem. The energies of the nuclear scientists and engineers would be focused on doing good things for their country – such as nuclear medicine and nuclear electricity, along with helping to dismantle the military complex and clean up the complex. During my various visits to Yongbyon, I had such discussions with their nuclear officials. They expressed a strong desire to have their technical personnel contribute to peaceful uses of atomic energy.

SisaIN: You described the 10-year road map as an 'interim' step short of completed nuclearization, designed to "reduce the nuclear threat significantly." Does it mean that the current denuclearzation talks should focus on reducing North Korea's nuclear threat significantly, not complete denuclearization?

Hecker: The road map integrates the short and long term actions to reduce the greatest military threats first and then eliminate all of the military threats in the longer term. Cooperative conversion would allow complete military denuclearization while providing assistance with civilian nuclear and space programs.

SisaIN: The Trump administration wants some sort of specific and fast denuclearization such as getting their nuclear warheads or nuclear weapons out of North Korea, etc. Is this possible? If not, what would be your idea for 'fast' denuclearization that could satisfy the US demands?

Hecker: First, taking nuclear weapons out of North Korea is too dangerous. They should be verifiably disassembled in North Korea by the same North Korean technical experts that assembled them in order to avoid an accidental nuclear detonation. Once safely disassembled, all components besides the plutonium or highly enriched uranium bomb fuel can be disposed of quite readily. Plutonium and highly enriched uranium should be either shipped out of the country or otherwise verifiably disposed.

As for fast denuclearization, what is important is to begin to roll back the nuclear weapons program. First, make sure that it does not get worse – so no more nuclear tests, no more long-range missile tests and no more production of plutonium or highly enriched uranium. With our concept of civilian conversion, the North should be encouraged to speed up the timetable we laid out in our roadmap. In other words, some of the North’s actions in the roadmap should be front-loaded. North Korea has already done some of that by closing the nuclear test site. Several other actions such as making the 5 MWe reactor permanently inoperable could follow quickly. These actions would reduce the military threat and could speed up the timetable.

SisaIN: When you observe President Trump's current denuclearization negotiation with North Korea, what do you think is the best possible realistic goal he can achieve during his term?

Hecker: Following the opening created by the initiatives of President Moon Jae-in and Chairman Kim Jong-il, President Trump has already taken the most important step to meet with Chairman Kim at the Singapore summit and move the Korean peninsula away from the brink of war. If his administration supports civilian conversion over the next two years, he could dramatically reduce the threat posed by North Korea’s nuclear program and create the conditions that will help to bring an end to seven decades of enmity on the Korean Peninsula – it would be a historic achievement.