We all must decide for ourselves the meaning and significance of the smile.
I have read the book, the screenplay, the dialogue transcript and watched the film several times. I would prefer it if things after 1933 actually happened rather than being a dream.
If like me you don't agree with the opium dream theory, I am not sure how you can say that Noodles is smiling in 1933 because of something that happens in 1968.
The book does throw up a few thoughts:
- what was Harry Grey/Goldberg's real name? - are most of the facts in the book true? - did Max actually dupe Noodles in real life? - why was he in Sing Sing prison? - what did he do after 1933?