A FEW SUMMERS ago, scores of people packed into a Beirut concert hall for an evening of nostalgia. An Iraqi-born singer performed songs by Umm Kulthum, Egypt’s most famous diva. “The Lady” was an icon of Arab nationalism: a champion of the Palestinian cause and friend of Nasser, who often scheduled his speeches to follow her monthly concerts. On this evening the mostly Lebanese crowd was drawn from a mix of sects and classes. Some wept through “Enta Omri”, a love song that seems to speak to today: “Your eyes took me back to the days that used to be/they’ve taught me to regret the past, and its wounds…”