Geopolitics have long intruded on the Eurovision Song Contest. But they were not really a factor as the event prepared to expand into Asia for the first time. That was still true as of Saturday evening, as the inaugural Eurovision Song Contest Asia was about to start in Bangkok. Over the decades, Eurovision organizers have insisted that the contest is nonpolitical. Its organizers impose rules governing lyrics, political symbols and what can be broadcast. Even so, wars and diplomatic disputes have shaped who gets to sing, who stays home and…