WASHINGTON (Reuters) – The United States voiced concern on Friday at China’s actions against the National Basketball Association, after Boston Celtics highlights were absent from a Chinese streaming platform following a player’s online criticism of China’s treatment of Tibet. Celtics backup center Enes Kanter this week tweeted a video of himself expressing support for Tibet and wearing a T-shirt with the image of the Dalai Lama, its exiled spiritual leader. He called Chinese President Xi Jinping a “brutal dictator.” Kanter was pilloried on Chinese social media and only a written timeline of hi…