A reasonably sized pocket knife is a versatile tool. It shouldn't be thought of as a weapon.
People who carry a "tactical blade" for "self defence" have obviously never read any case law around the use of knives in an attack. Let me just say that if you don't absolutely think you're going to be murdered, don't pull a knife. If you are at risk, go ahead and pull the knife, use it, and enjoy your jail time. Try explaining in court that you had it on you to open mail, or slice your apple at lunch.