“This is a an incredible transition.” Mario Mancuso, a visiting senior fellow at Hudson Institute, joined WTOP to discuss the soft diplomacy behind D.C.’s soon-to-arrive pandas. It may not be the biggest development in diplomacy since Nixon went to China. Two-year-old Qing Bao (left) in her habitat at Dujiangyan Base in Sichuan, China, and two-year-old…