Frenchy,
Europeans realize that pistols are secondary weapons. Many police forces, such as those in Spain and Italy, have the police commonly armed with submachine guns. In places like England, while the foot patrols go about unarmed, special teams can be put in place within minutes. Posse comitatus doesn't exist in Europe, therefore the military, with its greater firepower, is often fielded quickly during police emergencies.
Changing over to a new caliber begs the question, what do you do with the millions of rounds produced for previous pistols? The Customs Service faced the same predicament here in the US, and for this reason despite wanting to go 40, it stayed on with the 9mm.
European countries tend to have national standards for police equipment. Agencies simply don't have the flexibility in choosing equipment like they do here. Therefore US police forces have always led the way in terms of adopting new equipment.
Yet the 9mm is giving way. The 40 is currently being tested in Germany as a possible alternative to the 9mm.
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"Get yourself a Lorcin and lose that nickel plated sissy pistol."