On one hand, Diesel seems too important to ban. On the other hand, I don't understand how it wasn't already illegal for a long time. I don't need to see a Dies

On one hand, Diesel seems too important to ban. On the other hand, I don't understand how it wasn't already illegal for a long time. I don't need to see a Diesel truck to know one is upwind within a few blocks because the exhaust makes it hard to breathe. I've always just assumed it must be just me, or I have undiagnosed asthma or something.