After living in the Boston area during part of the Whitey Bulger years: yes. Yes, the fear becomes an almost palpable thing sometimes. Because you aren't just afraid of something that might happen. You know that people have been killed in retaliation. You've seen it on the news. Maybe you happen to work with the sister of a waiter whose only crime was being at work when a gangster was gunned down at his table. Maybe you knew one of the girls who was grabbed leaving work, dragged to a hotel room, and raped repeatedly because one of the gangster's bodyguards took a fancy to her. Maybe you were afraid to take your dance-loving daughter to see the Nutcracker because you'd have to park in the part of town where the parking garage was still taped off from a previous shooting. Or maybe you just saw on TV where the guy gunned down in the parking garage was believed to have been an informant but turned out not to be.
Yeah, this kind of violence does not just affect the people doing criminal things. It's like a cancer and the whole community dies a little every day.