It looked like a spontaneous tribute to Russia. Standing in the bombed-out shell of a theatre in the Ukrainian city of Mariupol, a Chinese opera singer, Wang Fang, belted out a Soviet-era ballad (pictured). In March last year many Ukrainian civilians were killed in a Russian attack on the building. So when a video of the 38-year-old’s performance this month circulated online, it sparked a furore. Unlike their government, some Chinese people prefer to side with Ukraine. To be sure, there are many Chinese who back Russia. News of the latest manifestation of China-Russia friendship—a meeting in Vladivostok between Russia’s...