When St. Petersburg’s renowned Mariinsky Theatre Orchestra performed Bach in the ancient ruins of Palmyra in Syria in early May, days after Syrian and Russian forces had forced Islamic State fighters to retreat, the Kremlin pulled off a media masterstroke. Millions of TV and Internet viewers around the world saw Russian power — military and cultural — defeating the barbarism of the Islamic State. Before the Islamic State’s expulsion, the terror group destroyed parts of the UNESCO World Heritage site and used its Roman ruins as a backdrop for beheadings and executions. On May 14, however, that same Russian regime was musically mugged at the Eurovision Song Contest by Susana Jamaladinova — known as Jamala — a Crimean Tatar who won by singing about Moscow’s oppression of her kin. …