it became more prominent because the black power movement technically started the peaceful civil rights movement. Americans noticed that it wasn’t just the African Americans that needed independence, but other ethnicities (bringing peace to all)
Thoreau, an important Transcendentalist, believes that people need to live an honest life. This can be applied to McCandless because he lived a few years of his life with nearly nothing. He disposed of all of his possessions because he simply thought they were unimportant in life.
I hope this helps you.