What are the Chagos Islands and why does Trump think Britain would be stupid to give them up?

By Christian Edwards, CNN (CNN) — Donald Trump has accused the United Kingdom of “stupidity” over its plan to hand over ownership of the Chagos Islands, including the US air base on Diego Garcia, to Mauritius. “Shockingly, our ‘brilliant’ NATO Ally, the United Kingdom, is currently planning to give away the Island of Diego Garcia