> There's a reason why every developed country in the World strictly controls firearms but not knifes.

As a slight tangent, Britain actually does strictly control knives - a short folding non-locking penknife is the only knife that can be carried in public without good reason, and “self defence” is considered never a good reason, and the penknife can still get you arrested if you happen to have it on you in an inappropriate place (bar, nightclub, sports event, etc).