No, it's the level at which people not eligible for vaccination are no longer at risk because most of their peers are incapable of spreading the disease. The political aspects are just some stuff some people made up.
Herd immunity is when Rt = 1, or 1 - 1/R0
It is the point when infections begin to decline due to acquired immunity.
https://royalsociety.org/-/media/policy/projects/set-c/set-c...