As Washington pulls back from its decades-long role as the world’s leading aid donor, the humanitarian system is facing what David Miliband calls a “very big shock.” On GZERO World, the International Rescue Committee president and CEO tells Ian Bremmer that the US has historically been the anchor of the global aid system, contributing nearly $4 out of every $10 aid dollar. But amid the cancellation of USAID and a dramatic pullback in foreign funding, vital programs are now closing and the impacts are being felt all over the world.