There's a balance between what "should" be carried and what will be carried.
Under perfect circumstances we would all carry a caliber that started with a 4 and ended in a 5 (or a 1 and 0 respectively) in a >14 round capacity magazine and carry a couple of spare magazines.
Except most would end up not carrying at all most of the time when we tired of the weight and the limitations of how we carried it.
Some would argue that the same load-out in a caliber that started and ended with 9 would be the alternative. 3 magazines of >13 rounds of 9mm "should" be carried. Until it too became too inconvenient and we left it at home for short trips (and then longer trips).
The forensic data is that the overwhelming majority of civilian self defense shootings involve less than our firing three rounds and that caliber plays a lesser role in stopping an attack than presenting the weapon quickly and making the first shot accurately. It isn't what we on gun and self defense forums consider intuitively obvious, but it is what real life data tells us.
So, when people discuss carry and capacity, the arguments often focus on worst case theoretical situations and on "perfect" circumstances (perfectly good and perfectly bad) instead of what they will practically do in reality in a less than perfect world. The basic reality is that a good gun carried all the time is better than a "perfect" gun carried part of the time.
I started as a "some is good, more is better, and too much is just right" P14 .45 carrier loading a +2 P14 mag with two spare standard magazines. 15+13+13 (41 rounds of Golden Saber .45ACP). I then carried an 8 round Colt LW Commander with two spares. I now carry either a Colt New Agent in 9mm with a +1 base or a customized 9mm alloy P35/High Power with a "Detective" size upper on the Belgian lower half and a 17rnd mag and one spare 15rnd magazine. I've also been known in shorts and Aloha shirt to carry a .380. It does no good to have a >17 round wonder cannon as your perfect carry gun if you won't carry it.
Under perfect circumstances we would all carry a caliber that started with a 4 and ended in a 5 (or a 1 and 0 respectively) in a >14 round capacity magazine and carry a couple of spare magazines.
Except most would end up not carrying at all most of the time when we tired of the weight and the limitations of how we carried it.
Some would argue that the same load-out in a caliber that started and ended with 9 would be the alternative. 3 magazines of >13 rounds of 9mm "should" be carried. Until it too became too inconvenient and we left it at home for short trips (and then longer trips).
The forensic data is that the overwhelming majority of civilian self defense shootings involve less than our firing three rounds and that caliber plays a lesser role in stopping an attack than presenting the weapon quickly and making the first shot accurately. It isn't what we on gun and self defense forums consider intuitively obvious, but it is what real life data tells us.
So, when people discuss carry and capacity, the arguments often focus on worst case theoretical situations and on "perfect" circumstances (perfectly good and perfectly bad) instead of what they will practically do in reality in a less than perfect world. The basic reality is that a good gun carried all the time is better than a "perfect" gun carried part of the time.
I started as a "some is good, more is better, and too much is just right" P14 .45 carrier loading a +2 P14 mag with two spare standard magazines. 15+13+13 (41 rounds of Golden Saber .45ACP). I then carried an 8 round Colt LW Commander with two spares. I now carry either a Colt New Agent in 9mm with a +1 base or a customized 9mm alloy P35/High Power with a "Detective" size upper on the Belgian lower half and a 17rnd mag and one spare 15rnd magazine. I've also been known in shorts and Aloha shirt to carry a .380. It does no good to have a >17 round wonder cannon as your perfect carry gun if you won't carry it.