@Bury Red no one said there is no gang activity in the UK, but the levels are completely different. Quite a lot of what I know about American gangs is from a cousin of mine who lived in Chicago, not from TV. The reason isn't the lack of guns, it's the fortunate circumstance that the UK does not directly border any failed states like Mexico which allows gangs from South America to spread, or (until recently) the kind of ethnic separation you get in the America. More to the point: the United States is the largest drug market by quite some distance. Not to mention they have been at perpetual war since they entered the Second World War, so there's thousands of violent psychopaths produced every year.
Sure, your estate was bad. But it's not South Side Chicago. I've lived in estates in Hackney and Woolwich and they were insane from my perspective, but I'm under no illusions about comparing them to the US. We haven't there, not yet anyway. Hopefully never.
Anyway, like I said, this discussion isn't really going anywhere. So let's just leave it.