The video flashed around WhatsApp groups, Twitter and Facebook. Shot at a Chinese-owned copper mine in the Democratic Republic of the Congo, it showed two men screaming and writhing on the dusty ground as soldiers kicked and whipped them, while helmeted managers watched. It was one of many videos and photos that went viral on Congolese social media in recent months – some real, some fake – all provoking outrage at the alleged mistreatment of local workers by Chinese mining companies. The backlash against the Chinese miners has been rising this year, even as they face another threat: a decision…