BEIJING—A series of photos published last month by Chinese state media of Foreign Minister Wang Yi standing shoulder to shoulder with visiting Taliban officials decked out in traditional tunic and turban raised eyebrows on the country’s social media. Since then, China’s propaganda machinery has quietly begun preparing its people to accept an increasingly likely scenario that Beijing might have to recognize the Taliban, the radical Islamic movement that is rapidly gaining territory in Afghanistan, as a legitimate regime. “Even if they can’t control the whole country, they would still be a significant force to reckon with”, an influential social media commentator known to be familiar with China’s foreign policy thinking wrote on Thursday. The commentator, who goes by the pen name Niutanqin, or “Zither-Playing Cow”, made the remarks on his WeChat channel. On Friday, the Global Times, a major state-backed tabloid, published an interview with the leader of an Afghan …