Maybe we've covered this in the past: I'm not sure.
I often caution folks who want to carry a knife for self-defense. This is not because I am not perfectly aware that knives can be quite effective on flesh, but because our culture seems to have gotten this weird idea about knife on knife duels.
Knife duels are just silly. Silly to contemplate, and damn silly to be involved in.
Distance is your friend. The firearm has two advantages over almost any other weapon system. The first advantage is short train-up time, since it takes less time to become dangerous than almost anything else. Before the advent of reliable firearms, months or years were required to become truly proficient with any weapon. 30 minutes of explanation and weapons familiarization, and a hour at a range, and a person can be dangerous to attackers with a firearm. Yes, practice will be needed, but that same amount of time with most other weapons systems will give you much less return.
The second and most important advantage of the firearm is distance. The more highly trained, vicious and effective your attacker is, the more important keeping them from closing with you becomes.
If a firearm is not an option, anything to deliver force over distance to an attacker should be used.
How NOT to use a knife.
Should one be without a firearm, and feel the need to use PLF (I'm going to call it potentially lethal force, because the use of even so-called lethal force weapons is usually survived), the knife should almost NEVER be displayed. Small knives are tools to be used against attackers that DO NOT know you're armed with a weapon. If a small knife is displayed and brandished, a potential attacker, even if not previously using a weapon, will most likely escalate to one. (This is part of the reason I laugh, somewhat sadly, when folks talk about the "intimidation factor" of a particular knife. Your honor, I was badly intimidated by the deceased. He scared me badly. Why did I shoot him ten times? Your honor, I ran out of ammo.)
Other weapons are usually preferable to knives for defensive use. The best way to use a small blade defensively, is when one has somehow been taken by surprise, or been overcome and taken down in a life threatening situation. In those cases, a knife can be used to cut the way clear. Because it will need to be instantly accessed, knives used for this purpose should be accessible.
This is why I feel the Daily Carry Knife should usually have a pocket clip and quick opening mechanism. Like a holster for a handgun, a clip can hold a folder in a familiar and instantly accessed place for right damn now use. Depending on how you've been attacked, your enemy's hands might be an ideal target for a cut, especially if one or both is holding you. DO NOT LOOK at your target if in this situation.
Maintain situational awareness. Look at your enemy if he's facing you. Don't look in his eyes, look about as his eyebrows with an open gaze so you can see as much of his movements as possible.
I am of course not talking about simple misunderstandings between friends, I am talking about life and death. Have a plan before you get into trouble. Then try not to get into trouble. If you do get into trouble, if you have several programmed responses to certain attacks, you don't have to consciously think about those responses. They're already trained in, so your mind is free to do other things like figure out how to escape and evade once you're clear of the immediate threat.
There is only so much that can be taught without direct interaction. Knives have a place in the defensive pyramid, but they're the tools you may have to use when you're about to have your lights put out, perhaps permanently. If you're using a knife, things have probably gone very bad. Learn some effective targets with knives, and carefully practice cutting, but learn other things, like running, how to use pepper spray, medium to large dogs, firearms, canes, and even by god, vehicles, if it comes to it.
Y'all be safe out there.
John
