"Recently, an elderly man was beaten on Chicago public transportation first by a pickpocket he caught in the act and then by a mob ... you can't use deadly force to defend against a less than deadly attack."
And that's Chicago.
In Tennessee carry permit class based on actual court rulings and opinion of the state AG, "less than deadly attack" meant something like a bloody nose, black eye, boot bruised butt from which you could expect to walk away maybe with bruised body or ego but with no imminent threat of death or permanent disability. Disparity of strength or size (an Arnold Schwartzeneger beating a Wally Cox) or disparity of numbers (a gang jumping a lone person) would constitute a deadly attack justifying threat or use of lethal force in self-defense.
FBI: UCR 2018 Crime in the United States
Expanded Homicide Data Table 8 Murder Victims by Weapon used
672 Personal Weapons (hands, fists, feet, etc.)
297 Rifles
235 Shotguns
So the 672 murder victims killed in 2018 by unarmed assailants using personal weapons (hands, fists, feet, etc) should have been felonized if they had defended themselves with a deadly weapon and survived? (And if assault weapons, a subset of rifles and shotguns, are to be banned, what about those more often lethally used personal weapons?)
There are nuances in law and precedence in Tennessee: the initial attacker has the duty to retreat; if the attacker decides to leave, the victim no longer faces imminent death or greivous bodily harm and has successfully defended themself within the law. If the initial victim continues to use lethal force in retribution or pursues the attacker for revenge, the legal roles are reversed and the retreating attacker has the right to use lethal force in self-defense if they fear for life or limb.