Edit: this is in America. In Eastern Europe, where petty theft was widespread, I’d only do it in upscale locations (e.g in the de-facto ‘embassy’ district) or when I was friends with the staff and could trust them to keep an eye on my stuff.
(probably other examples too. This just floored me as an American)
(The link in the article you posted mentions 97 cases of abductions; it's important to note that 100% of abduction cases involve the child's family, e.g. in custody battles and similar. A kid getting snatched off the street is a once-in-a-decade thing or rarer, and it's never an infant.)
Pickpocketing is only a concern in tourist traps like if you went to visit the tower of Pisa out something.
And waking around my university buildings, it's very common to see people leaving their stuff including expensive laptops to reserve their spot in the library and random tables in hallways that have them. Though this is frowned upon if you're going for more than a few minutes.
I have not spent a huge amount of time in Europe but judging from the way certain minority groups are spoken about by many Europeans, it is not a widely held belief in Europe that pickpocketing is limited to tourist areas - although I'm sure that's mostly true.
It’s always a culture shock for me to travel to other places in America and see bars on store windows, homeless people, signs telling me not to leave stuff in my car. I can’t understand how people let things get that way or why they allow it to continue.
We already live in a surveillance state - there's cameras everywhere and the police can use your phone's location data pretty much willy-nilly.
So the net result is some Americans are already living in a surveillance state and don't even get the touted safety benefit.
People in places like this need to take a good, hard look at what causes society to break down in this way. People all through this thread want to blame things like safety nets and not enough money...I live in a very poor area in a red state with basically no safety nets beyond the federal minimums. Would I like more safety nets? Yes. Is the lack thereof the cause of crime? No.
If a brief period of extreme policing though is necessary to change the culture and incentives, maybe it's worth it though, especially given the fact that statistics show that most of the problem is people continually reoffending. Why would you want to live in a low-trust society where you have take being robbed as a real risk? What kind of knock-on effects does that have? People talk about car culture, for example - doesn't that reinforce it? How does that affect kids? Neighborhoods and communities? Anxiety and depression? It's just such a huge negative it's mind-boggling to me that people tolerate it and justify it.
Probably not.
The new security threat that campuses are concerned about is right wing terrorism.