But they entered the public awareness in 1963 with the March on Washington, and haven't let up since.
My concern is that if, Heaven forbid, there is ever again something worth protesting to that degree, no one will pay attention. Regular Americans, rather than being swayed, will look on and say, "Oh look honey, the kids are protesting again."
Survivorship bias ensures that history only remembers the protests that were meaningful, making it seem like protests were historically more effective and more meaningful.
I don't think they are as "enshrined" as you think they are.
Or one could observe that it has completely let up and now most Americans are cynical about protests and cheer on authoritarian figures from both parties.
but probably what you are referring to is post world war 2, which mostly started in the 1960s caused by the vietnam war and civil rights movements brought about by myriad causes (middle class affluence, mass communications, overextending of the govt overseas (and at home with the draft etc))
wikipedia, but it’s as god a place to start as any[1]
I'd love to hear other perspectives.
Women protested in the 1910s for the right to votes.
My guess is it’s an industrial revolution side effect, but would be love to learn of earlier roots.