Now it seems to me that Britain is far more tolerant of general street thuggery than the US, both in terms of general social attitudes, and in terms of law enforcement.
Those in the UK may not realize this, but in the US, one can get a conviction and jail time for shoving or even touching someone else, or merely threatening violence. The police generally do NOT just say, "Boys will be boys," and intoxication is generally not an acceptable defense.
Our bar scene here involves very little violence, and we as a society don't tolerate it. Ditto for our professional sports events.
We really aren't a crazed cowboy culture of bar brawls as some Europeans seem to believe, not in the least. We may not be as polite as the Canadians, but here we think of steel-toe boots as something your boss or your union rules require at work, not as weapons. Most people take them off before going out for a beer.