Yes, for years it was the Jewish-American party tune, heard at numberless weddings and bar mitzvahs. But those years were the 1950s, ’60s and ’70s, and now the song is profoundly uncool. Says one mother-of-the-groom, “‘Hava Nagila’ at a wedding is like pouring sour milk on cereal.” An ethnomusicologist calls it “a really crummy little tune” that became “the equivalent of a knish.”