linowell & Woodsman,
With proper or lucky placement the 38 Special or the .380 will take down anybody, but so will the .22 short. More powerful platforms offer more margin if you miss the central nervous system. I just suggest that if circumstances require carrying a smaller weapon that the person give even more thought as to how he might handle a situation if his primary weapon doesn't give him the stop he needs.
As for the 38's and 380's being used for a long time, that is absolutely true. All a person has to do is look at the civilian sales records over the past century for the little calibers, especially 38 Special as compared to say 44 Special, 45ACP, and 45 Colt, and he can see how much more popular the 38 Special was and probably still is. If the .380 took longer to gain broad acceptance, it was probably because people were longer in accepting semi-autos and not because of the power of the cartridge.
I probably shouldn't have said anything about the marginal power of the 38 Special and the 380. Nothing I said is new information, and anyone interested can find more opinion and tests on the relative merits of those cartridges than they would ever want to read. I should have known better. People don't like hearing doubts expressed about their favorite cartridges. I'm probably as bad as anyone on that score.