Here is what I posted when Jaystarr posted a similar question. Hope it helps:
I don't know anything about wartime Polynesian or Tonkinese society, but I've always assumed that parents arranged marriages and choose partners based on financial considerations as much as anything else. That is why a wealthy planter would be an advantageous and reasonable choice, whether or not there was any actual "love" involved.
As aliciag correctly points out, Bloody Mary is a capitalist. With her new found financial freedom Bloody Mary can afford to marry off her daughter to a man who would make her daughter happy. She sees something in Cable and just "knows" that he and her daughter would be a good match. And judging from their reaction to each other, she was right.
The fact that Bloody Mary would consider a man outside of her race dramatically contrasts the racist mentality that Cable is wrestling with.
So I don't see it as Bloody Mary putting the white race on some superior level. I see it as part of the over-all power of love theme that runs throughout South Pacific.
As for the race issue being out dated. I can't agree. I haven't seen this production yet, but I know the show pretty well. The way Hammerstein handles the race issue is so smart and so brilliant. He doesn't make his character clear cut, easy to hate bigots...but likeable individuals struggling with what they have been taught vs what their hearts tell them is right. That dilemma is as much a part of the human condition today as it was then.
What great ones do the less will prattle of