The key to the success of Shaft is the universal appeal of the main character.
Shaft is black and commands the respect of the black community.
That respect is gained through his ability to survive without subjugating himself to the white authority figures. Shaft is not intimidated by the police, the mafia, or even black gang boss, Bumpy. Shaft is free from the confines of race, he neither bows to nor wants to subvert white society. And in the early years after the civil-rights upheavals of the late 1960's, freedom from the boundaries of race was everyone's dream. This was also a time when black Americans were finally claiming the rights that had been denied them for three hundred years.