Why is it that what was good enough back then isn't good enough now?
I'm talking about calibers. Once upon a time, it seemed that .32 acp was an acceptable round for police and military use. Then came the .380 acp (AKA 9×17mm, 9mm Browning, 9mm Corto, 9mm Kurz, etc). But that was replaced by multiple modern calibers.
Why was .32 acp considered good enough when the .45 acp was around? Was it because of the guns in use at the time, manufacturing capabilities, politics? I don't know the answer, so I'm hoping for some education here.