In Let the Great World Spin, what does "Remember 'nam, Sam" mean, or what does it refer to?
This slogan occurs in the prologue of Let the Great World Spin which takes place in the 70s in New York. There is a crowd of people looking up at a man standing at the precipice of one of the towers, and they are trying to figure out what is he going to do. One of the possibilities is that he is going to hang a slogan and this is one of those that are mentioned. I am not a native speaker, so I would really appreciate any suggestions as to what could this mean. Thank you.
Whenever you come across the term "Nam" in American English, it refers to Vietnam. So this is just an anti-war slogan.
As you say, this is one of the things people think the man might be doing. He might be putting up these protest slogans. All of the slogans are opposed to the Vietnam War.
The word "Sam" can be interpreted in two ways here. First, you can identify it with "Uncle Sam" -- another name for the United States. Or it might just be used to rhyme with "Nam." In other words, it would be used to make the slogan more catchy -- like "Get back, Jack" or "even Steven" -- both of these are cases where the name is only included to make a rhyme.
Whichever way you want to read the word "Sam" this is an anti-war slogan because 'Nam refers to Vietnam.