“The cracks seem to run deep. But at Eurovision — and the many preview events, such as the one in Moscow that I went to in April — I regularly see a vision of Europe where fans across the Continent, artists and their entourages are more connected than ever. This year’s contest, which includes two semifinals and culminates in a grand final next Saturday, will once again celebrate the diversity of European pop. It will also provide a space for outsiders, including a huge L.G.B.T. fan base and many upstart artists, to feel mainstream.”