The idea of a personal "arms race" comes up from time to time. That may be valid when it comes to "good guys carrying guns" but only in that guns as a category are at the top of the food chain. It's worth considering that among guns, a battle rifle is obviously more effective than a pistol, a full-size duty pistol may be more effective than a compact, etc. Most civilians who EDC a gun in America tend to carry things that are more comfortable to lug around all day. For instance, I often carry a lightweight, short-barreled, six-shot revolver.
The reality for bad guys in America is that they could have anything. It could be a gun. It could be a knife. It could be a length of copper pipe. In some cases, it could just be a big, strong, muscular body. The motivations for their violence can be pretty diverse (theft, drugs, revenge, road rage, sexual assault, mental illness, etc.). Meanwhile, the "good guy" or intended victim could be a man, a woman, someone old, someone disabled, etc.
So going to the top of the chain on defensive tools, relative to what you can carry as a civilian, increases effectiveness against the greatest possible breadth of risk. It's also worth noting that many violent crimes are opportunistic. So considering the diversity of tools for violence and the diversity of potential victims, having the top tool can be an incredible equalizer. Knowledge that a "little old lady" might have said equalizer in her purse can itself act as a powerful deterrent to some kinds of violence.
It makes sense, relative to the level of threat.
When the potential risk of aggresion towards you and your loved ones is relatively higher, wanting to protect one self becomes a bigger priority.
Let me ask you this:
Lets say, you were invited to visit Denmark.
How would about feel, walking around Copenhagen, unarmed?
My initial post was never a stab at your choices to be armed. Nor a stab at your 2nd Ammendment.
It was more a reaction to the circumstances, which makes many of you deem it necessary to be armed and carry knives for self defense.