It’s easy to imagine what drew composer Tim Rosser and lyricist/librettist Charlie Sohne to bacha bazi, the subject matter behind their new musical, The Boy Who Danced on Air. The lives of Afghani “dancing boys,” poor young men conscripted by the wealthy into sexual slavery, offer high-stakes drama and political topicality. Though spirited and nuanced, though, the play lacks the caution, finesse, and heterogeneity necessary to avoid joining the ranks of American musicals that have tried to absorb non-Western cultures, only to abuse and debase them (which is pretty much all of them).