Firearms have not routinely been carried during my lifetime, by the public or by the Police. The laws were tightened following a number of atrocities relating to licensed firearms, many of which it is now illegal to own. I seem to remember that the firearms that were allowed prior to this were for shooting clubs and suchlike and were not allowed to be taken out of those clubs, not sure though. Either way, we have no guns and have a very low homicide rate where guns are involved, according to
wiki:
"In the United Kingdom in 2009 there were 0.07 recorded intentional homicides committed with a firearm per 100,000 inhabitants; for comparison, the figure for the United States was 3.0, about 40 times higher"
To be honest, it would scare the crap out of me to see certain people in the UK being legally allowed to carry firearms, with our current binge drinking culture Friday and Saturday nights would become very dangerous indeed!