Why does China care who the next Dalai Lama is?

Sky News Daily

The Dalai Lama, Tenzin Gyatso, is turning 90 and has confirmed - after years of uncertainty - that he will have a successor after his death and will not chose to end the line.
In Tibetan Buddhist tradition, the Dalai Lama is reincarnated after they die. Monks search, select, and school a successor – usually a child. The current Dalai Lama was recognised at the age of two. He and an estimated 150,000 Tibetans now live in exile in India, and other countries, after China annexed Tibet decades ago.
And that makes who the next Dalai Lama is, a concern of China's.
Joining Matt Barbett is Professor Robert Barnett, who founded the Modern Tibetan Studies Program at Columbia University and is now at University of London's School of Oriental and African Studies (SOAS). He has also met the Dalai Lama several times.
Producers: Soila Apparicio and Emma Rae Woodhouse
Editor: Wendy Parker