? Japanese subways were infamously the site of a nerve gas attack in the 90s. 33 people were killed in mass knife attacks in Kunming, China in 2014. France has had a handful of subway and train attacks.

However, the point is that these incidents, along with the BART one, are unusual. Avoiding public transit because of them would be like avoiding flying because of air accidents or avoiding going to a theater or musical event because of the various massacres that have happened at them over the years.