Jeff Cooper remarked in one of his "Commentaries" that Hans Rudel
only carred .32 Mauser pistol. I'm guessing an HSc.
When Colonel Cooper questioned him about it, he remarked that by the time it came down to the pistol, caliber was largerly esoteric, or words to that effect.
Now granted, he was an attack pilot, so he did his fighting with a Ju-87, I've always found that comment telling.
Also, based on my limited readings concerning European police forces, for the most part they carried what we Americans would call "mouse guns" right up until the late 70s. The Munich Olympics being the deciding factor there.
Also, I've noticed that European police forces are much more willing to have foot patrol officers out and about with long arms, something we as Americans don't expect to see except in times of civl unrest.