I read too many cases of child abductions in my early criminology days. The James Bulger case terrified me for years. Or imagining the absolute horror of a parent whose child has been stranger kidnapped and might be anywhere, going through god knows what terror. I would love to feel that sense of trust/community that those Japanese societies must have.
I know the statistics are tiny, and super unlikely. But still, the absolute fear, when you are at the shops and momentarily lose your child, its heart-stopping. The stakes are so high, and I think i'd torment myself forever if something happened to him that I may have been able to prevent had I been there.
With my DS now a strapping 11 yr old, (5'4, and 115 lbs), he is probably big enough to do more on his own. I let him stay home for 15mins if I'm walking the dog around the block, he races his bike the last block or two home alone. I'm getting more comfortable as he becomes more physically able to defend himself, able to problem-solve and reason, not freeze in an emergency, and speak confidently to adults (he was a quiet, passive younger child). I feel like that if, god forbid, someone tried to entice him/physically harm him, he'd have a decent shot of helping himself to survive.
I don't regret the 'helicoptering' though, in this aspect. Kids are kids for such a short period of time.