This is also how it's done traditionally in Ireland, the regular police aren't armed but there is a "Special Branch" of detectives, usually plain clothes in unmarked cars.
Recently they've been sneakily expanding the use of armed police though. In Dublin, I see more and more cars marked "Armed Response Unit" which have regular cops with guns. And just last week a detective was shot and killed with his own gun while doing a traffic stop. There's been a massive PR blitz about how good a guy this cop was, but zero discussion about why the duties of armed police have now been extended to include road traffic policing. I suspect it's planned to arm more and more of them and I wouldn't be surprised if the British followed the same slippery slope.
Not particularly, Irleand is a relatively homogeneous country. There has been an uptick in the last few years in drug gang related murders due to a feud between two pretty brutal drug cartels (the leader of one now controls an international cartel from Dubai and rather outrageously is the promoter behind the Tyson Fury Vs Anthony Joshua heavyweight boxing fight). I think this has probably lead to an increase in gun carrying by Gardai (Irish police service).
Recently they've been sneakily expanding the use of armed police though. In Dublin, I see more and more cars marked "Armed Response Unit" which have regular cops with guns. And just last week a detective was shot and killed with his own gun while doing a traffic stop. There's been a massive PR blitz about how good a guy this cop was, but zero discussion about why the duties of armed police have now been extended to include road traffic policing. I suspect it's planned to arm more and more of them and I wouldn't be surprised if the British followed the same slippery slope.