That's my perception too. The thug element in the black community of my youth was very small - probably not much bigger than the percentage of thugs in the majority population. Every community has a few rotten apples.
When I was a kid, there were two forces kept that percentage to a minimum. Those were; the better moral fiber of the people in those days, and police departments that simply didn't let it get out of control.
As the gov't welfare programs of the 60s began to take hold in black communities, the first of those two forces (moral fiber) began to fray at the edges, and in time, nosedived on a crash course to complete disintegration. Now, more than 7 in 10 black children are born to unwed mothers - many of them teenagers.
Nearly all of those children have been born into such a bankruptcy of personal integrity and common sense morality, that they're easily led into the most degraded and destructive life choices imaginable. The sub-culture they know, is hardly recognizable to their grandparents and great-grandparents.