Hi csl,
Isn't that what we call a straw man argument?
You argue not against what is said but against what you construct instead.
The proposition that knives should be banned in public is different from the proposition that knife sharpeners should be banned in private. The latter does not make the former absurd.
The proposition that a person may not elect to carry a knife is different from the proposition that sharp objects must be banned. The former includes the concept of volition.
I think the same police officers who enforce the law with regard to weapons may be capable of considering a knife to be a weapon. So the cost of enforcement looks to be about zero.
If the restriction on carrying knives is absurd, it should be easy enough for you to argue against the carrying of knives, without making dodgy comparisons.
Why is a knife-carrying freedom necessary? Will concealed knives protect citizens against an out-of-control state?
Is a per capita weapon-related death rate in the US 40 times that of the UK and Canada not cause for concern?
Don't you feel just a little bit bothered by events like Aurora?