Remember the US is the nation of the helicopter parents, where it is common to drive the kids to school and everywhere else until they get their own driving license.

And cops are common to pick up younger kids which are around on their own because it is so unusual

Putting a kid on its own on a train would be absolutely unthinkable.

I rode trains through out my teen years in the USA. No issues!

And that world no longer exists.

Jesus. In Switzerlans i saw kids as young as 7 walk to school alone taking trams and walking.

"Kids can travel in trains alone."

Parents can't even let their kids walk to school alone. I seriously doubt they would allow their kids to ride a train alone.

That case was an aberration. That's why it became such big news. If that were the norm, it would not have become national news.

This said, helicopter parents are real. I've ridden on amtrak many dozens of times, but never saw an unaccompanied child.

The only time I used Amtrak there was a child in the opposite seat. Staff put a sticker over his seat announcing that he was alone, which I thought was odd.

Meanwhile round here in London children get free bus travel, so it's very common to see them on local buses, and sometimes trains (tends to be wealthier kids on trains).

I've seen many on Caltrain in the mornings but many many more in Japan.