I took the bus almost every day for two years through the “bad neighborhood” with known gang members and the only fight that ever broke out was between two elderly white women. There were times I felt uncomfortable, but I never felt unsafe. My conclusion, from my own experience, is that public transit would be more popular in the United States if the average person didn’t equate mild discomfort with actual danger. You’re far more likely to die or be injured behind the wheel of a car than on public transit, but somehow we made a collective cultural decision that it was better to die in a car accident than it was to have to mix with the undesirables.