I'm not sure which show the OP is talking about, because I saw Miss Saigon and I distinctly remember Robert Duvall (at least I'm pretty sure it was Robert Duvall) singing a song about how much he loves the smell of napalm in the morning while bombs fall around him. And then there's that ballet scene with the tiger who jumps out of the jungle, brilliantly choreographed by Julie Taymor. And let's not forget that intense act I finale that finds the Viet Cong forcing our protagonists to play Russian roulette while the chorus dances around them singing "They both reached for the gun!" Best night of theater in my life.