I was a liaison to the Joint Service Small Arms Program (JSSAP) at Aberdeen in 1978 when they were really pushing the 9mm as the new Personal Defense Weapon to replace the .45 and the USAF .38 special.
Some of the discussion was about NATO commonality and there a lot of cooked studies about 9mm lethality but the discussions also mentioned the difficulty women and men with small hands had with using the .45.
We Marines were strongly in favor of keeping the .45 but the army and Air Force strongly pushed the 9mm and specifically the Beretta 92 - to the point that when Colt, S&W, H&K, and others started to conform with the requirements, the army would modify the requirements to more clearly to match the Beretta, moving the goal posts.
Being a smart ass captain, I raised my hand and asked sir - is that the same 9mm the Germans lost two wars in a row with?. The army colonel in charge of the briefing told me to shut up and sit down, while we Marines laughed.
Never understood that. I taught my daughters to shoot a handgun with a .45. Both are 5'-2", and they both love the .45. Very, very easy to handle and shoot. Maybe a little noisy.