What does “a rope on a tree” mean?

Question

Bobby Seale, national chairman of the Black Panther Party and eighth defendant, says to Tom, one of the Chicago 7 group:

Bobby: The seven of you, you've all got the same father, right? You all got the same father, right? "Cut your hair…don't be a fag, respect authority, respect America, respect me." Your life, it's a "fuck you" to your father, right? A little?

Tom Hayden: Maybe.

Bobby: And you can see how that's different from a rope on a tree?

Tom Hayden: Yeah.

What does "a rope on a tree" mean?

Source: The Trial of the Chicago 7 (2020)

Answer 1

As the comment says, it's an allusion to lynching, murder by a mob in the form of hanging.
Wikipedia "lynching"

I think what is happening here is that Bobby Seale, a black man, is suggesting that his white co-defendants aren't as seriously committed to protests as he is. They are all rebelling against their fathers (characterized as essentially the same person) and so are sort of dilettantes at protest, while he, as a black man in America, has faced the danger of mob murder all his life.

Answer 2

I think what is happening here is that Bobby Seale, a black man, is suggesting that his white co-defendants aren't as seriously committed to protests as he is. They are all rebelling against their fathers (characterized as essentially the same person) and so are sort of dilettantes at protest, while he, as a black man in America, has faced the danger of mob murder all his life.

I'm pretty sure that's not what he meant at all. Bobby Seale knew that these people were committed to the protests and for the cause that they were fighting for. What he meant was that his fight is much bigger, much worse, and has been grounded in America for far too long and probably will be in the future. While he condemned American involvement in Vietnam, he didn't have the resources or time to waste on this trial while the ghettoisation of his community was destroying it from the inside and the pigs were hell bent on destroying whoever tried to fight for themselves.

His protest wasn't a fuck you to his father or part of a rebellious phase against the machine, his protest was survival, and ensuring his community survives - and he knew Hayden understood how it's different from the protest he was being accused of participating in.