> Public transit requires a certain level of unspoken agreement. "We will all behave in this manner."

That literally all of society.

The American idea that you live in suburban home that is a quasi gated community, drive into a parking garage, then go up to an office, only interact with workmates and then driving back out with no social interaction other then work is just not how most society worked for all of history. And its not how the US worked until the 1960.

The reality is, violence and death on the roads, is far more common then on public transport. There are tons road rage incidents, an absurdly high number. Those lead to all kinds of problems and quite often shootings. You are in more danger then on public transport generally. And yet I almost never hear about that when Americans talk about transport policy.

But yes, there does need to be rules enforcement. But on the other hand its also true that the US often has very user-hostile design principles in pretty much every aspect of their city design and policing policy. And that often invites or re-enforces bad behavior.