A phrase originally used in the late '60s and early '70s in support of the
hippie movement against the older generation's often prude and narrowminded world view, which
associated long hair (especially on males) with a sloppy lifestyle. Sometimes also related to long hair on males being associated with
homosexuality due to the similarity with traditionally feminine hairstyles. The phrase emphasizes that the speaker isn't affected by what is meant as an insult but actually embraces the accusation.