NATO (or the U.S. Dept. of Defense) does not believe that a sidearm is relevant or even particularly useful in war. They look at caliber as a purely logistical supply issue. Individual soldiers on the ground tend to have a completely different opinion on this. Unfortunately the people upstairs make the rules with no regard as to what the people on the ground think. The guys on the ground are irrelevant and expendable and don't cost much compared to the machinery of modern warfare.
