Lessons from Major Jeff Cooper on Knife Attacks By John Steele

     With knife attacks on the rise, almost everywhere, and knives being very hard to control, it would be prudent for people to begin to accept that we live in an unsafe, nay, dangerous, world and that it is necessary to adopt a philosophy of preparedness, or face this:
  https://vladtepesblog.com/2018/03/29/we-want-everyone-to-see-what-was-done-to-our-daughter/  

     The man to help on this is the late Major Jeff Cooper, the father of American pistolcraft, and self defence expert. He gave a colour code approach to navigating through the world that would be good for readers to have under their gun belts:

“Considering the principles of personal defense, we have long since come up with the color code. This has met with surprising success in debriefings throughout the world. The color code, as we preach it, runs white, yellow, orange, and red, and is a means of setting one’s mind into the proper condition when exercising lethal violence, and is not as easy as I had thought at first. There is a problem in that some students insist upon confusing the appropriate color with the amount of danger evident in the situation. As I have long taught, you are not in any color state because of the specific amount of danger you may be in, but rather in a mental state which enables you to take a difficult psychological step.

Now, however, the government has gone into this and is handing out color codes nationwide based upon the apparent nature of a peril. It has always been difficult to teach the Gunsite color code, and now it is more so. We cannot say that the government’s ideas about colors are wrong, but that they are different from what we have long taught here. The problem is this: your combat mind-set is not dictated by the amount of danger to which you are exposed at the time. Your combat mind-set is properly dictated by the state of mind you think appropriate to the situation. You may be in deadly danger at all times, regardless of what the Defense Department tells you. The color code which influences you does depend upon the willingness you have to jump a psychological barrier against taking irrevocable action.

That decision is less hard to make since the jihadis have already made it. He further simplified things in 2005: “In White you are unprepared and unready to take lethal action. If you are attacked in White you will probably die unless your adversary is totally inept. In Yellow you bring yourself to the understanding that your life may be in danger and that you may have to do something about it. In Orange you have determined upon a specific adversary and are prepared to take action which may result in his death, but you are not in a lethal mode. In Red you are in a lethal mode and will shoot if circumstances warrant.”

     All this can be reduced to the modified boy Scout motto: be prepared, or be prey. It is as simple as that.
  https://en.wikipedia.org/wiki/Jeff_Cooper 
  https://archive.org/stream/JeffCooperPrinciplesOfPersonalDefense/Jeff+Cooper+-+Principles+of+Personal+Defense_djvu.txt