The dismantling of North Korea's Yongbyon nuclear complex should not be underestimated in the denuclearization process, an American nuclear expert said Friday. Siegfried Hecker, known for his 2010 visit to the Yongbyon complex, made the remarks during a video conference with Unification Minister Lee In-young and Moon Chung-in, special foreign policy adviser to President Moon Jae-in, also stressing the need for a &qu...