It is a great movie, for sure. But it is a sad commentary on our culture that little of even nearly equal value has been produced in the almost 50 years since it has been made.
It involves two themes that progressives need to obscure:
1) the Von Trapp children were starving for love from a mother figure and found it with the arrival of their new governess (family nucleus)
2) A sovereign Austrian people (majority rule) voted to allow itself to be annexed by Nazi Germany, and a few courageous people saw the looming danger of a totalitarian state that they were willing to leave their homeland to save their family.
And maybe another theme —
A family — and especially the father, who love their country beyond compare.