In 1972, pandas arrived at the Smithsonian’s National Zoo in Washington, DC, to huge fanfare. Since then, pandas have been some of the city’s most beloved residents.But for the first time in more than 50 years, DC is panda-free—indefinitely. Mama panda Mei Xiang, papa bear Tian Tian, and their youngest cub Xiao Qi Ji returned to China in November when their leases ended. This is possible because all but a few pandas residing outside of China are on loan through agreements with the country.It’s not just the National Zoo waving its pandas goodbye—the Memphis Zoo’s single panda returned to China in April, and Zoo Atlanta’s pandas will go later in 2024. The news of the pandas’ departure seemed sudden, and it stirred up some questions: Why are the pandas leaving? And why now?The news resurfaced the idea of panda diplomacy—how China introduced pandas to the world by loaning them out to other countries and using them as a symbol of cooperation.SciFri producer Rasha Aridi and freelance journalist Aja Drain look back at 80 years of panda conservation, and how panda diplomacy paved the way for groundbreaking science. And they try to answer the multi-million dollar question: Was it all worth it?This story was produced by Rasha Aridi, with help from Aja Drain. Edited by John Dankosky, with help from D. Peterschmidt and Emma Gometz. All our music and sound design is by D. Peterschmidt.Special thanks to the experts we spoke with: Dr. Chee Meng Tan, Dr. Pierre Comizzoli, Dr. Mel Songer, Michael Brown-Palsgrove, Dr. Rich Bergl, Dr. Jack Liu, Dr. Binbin Li, as well as Dr. E. Elena Songster, environmental historian at Saint Mary’s College of California, and Dr. Carolyn Lin, professor of communication at the University of Connecticut.Transcripts for each segment will be available after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.