I'm a graduate of Massad Ayoob's "Lethal Force Institute".
Mas' rule #1 is "Don't go to the bad places..."
That tends to keep you out of trouble.
Now, it seems that the "bad places" are coming to randomly selected "good places"...
It's certain that the bad actors in these swarming events are bolstered by the confidence that the victims can't defend themselves.
I was raised in a town adjacent to Chicago. Just visited the area a week ago. Just into the city, I saw street scenes loaded with idle groups of young men hanging out together in the mid-day and up to no good. I left the areas quickly.
I like what Marc has to say about avoiding trouble. In fact, as a CC holder, you are even more obligated to avoid those situations. It's common sense even without CC. When I go into the city, I don't go outside of the lakefront, Streeterville, Michigan Ave, The Loop, The Gold Coast, or the areas around the museums. I have no problem driving directly to Soldier Field, McCormick Place, The Cell, or The United Center (I have no reason to visit Wrigley Field

). But I go directly there on expressways, main routes, and always use the big public parking areas. I have had no trouble taking the Metra train to and from the city and grabbing a taxi to/from where I need to be. I would never take the EL or the local trains.
I don't put myself into those bad areas, and know that getting even 1 extra block too far away from McCormick, the UC, or the Cell can get you into trouble (it only takes once to drive through off the beaten path to learn that).
But I don't go there.
So I guess that would qualify under Ayoob's rule. So when the "wilding" or "swarming" or "multiple offender incident" comes to the good areas, what are you to do? Avoid the good areas even though this behavior is not the norm? (And it's
not the norm even though the media would have you believe it is. Fear sells papers.) Should I move out of my awesome, safe subrub because a few doors down there was a home invasion tied to a drug deal gone bad? And I live in an affluent western suburb. Or what about the next town over where a family was the victim of a home invasion (the teenaged daughter raped while the parents were tied up)? And that was in a upscale neighborhood too.
There are two issues underlying this back-and-forth about Chicago.
1)
Concealed carry. My fellow Illinoisans, CC is coming -- I truly believe it. It's just not here yet. While it may make people feel safer, if you don't go into bad areas, the chances of ever getting into a fight are going to be small. I am not saying that it can never happen outside the bad areas. I am not disputing the fact that the Chicago politicians have made it nearly impossible to protect yourself inside the city limits. Not debating that at all. Something needs to be done to give that power back to its residents.
2) Chicago as a good or bad place. If you don't like it, please stay out, but don't give the impression that it is a horrible cess-pool that you are lucky to get out of alive every time you go in or that you need body armor in order to survive. Give me a break. Hang out on the west side, yeah you're obviously going to get into trouble. Walk on Michigan Ave., take a boat tour, and eat at Milennium Park before watching a concert and 99% of the time you will be just fine (just like the 99% of the time in my affluent neighborhood -- until news of a boyfriend gunning down his estranged girlfriend in her driveway hits the local papers).
Like Marc (and Ayoob) said, choose where you go carefully and most of the time you will be fine. And when you do go, be alert for that 1%.
Do people have a right to defend themselves? Absolutely!! But it all starts with common sense.