war, policing, defense, hunting, animal control, shooting down flying objects, remotely activating something from afar, immobilizing a car.
In particular, most societies deem automatic rifles to have no legitimate peace-time use, and so outlaw them, while still allowing shotguns and hunting rifles with a license.
b) One of the first and foremost items on gun-regulation todo-lists is to get rid of the kind of guns with the specific use-case of making killing people as easy as possible, aka. miltary weapons, automated weapons, easily concealed weapons, etc. So the regulations against guns are already targeting use-cases.
c) Physically controlling guns is a proven method, its effectiveness is supported by decades of evidence in countries implementing it.
Isn't that like saying theft cannot be regulated effectively without removing the things people want to steal from society? The goal is not perfect gun control, but reducing access to guns and thereby reducing the crime and harm that stems from gun ownership. So it being illegal to own X doesn't mean no one will own and use X, but that fewer people will and law enforcement will be able act against those who do.
this is exactly what people against gun control say