My mother thought that Carousel was the musical from America with the most heart. I used to know some of the songs of South Pacific because it was about war and war was a fantasy to a nine year old. Yul Brynner and Deborah Kerr dancing in the King and I is a glorious scene. The Music Man has a great finale. I suppose these and others were made to uplift and play on the emotions but I saw Once and thought it was extremely well done. No razzmatazz, no set pieces just melody and a gentle story.
Song is important. an extension of rhyme which once was the way to teach children to remember.