[Big Dave]

hal9999 posted:
"...did you ever live in a high polluted city ?"

Big Dave says:
Detroit, Chicago, Cincinnati in the 1960s. Johannesburg in the 1970s. Bangkok and Taipei in the 1990s. Polluted enough for you? I also worked on railroad ready tracks where 50-60 locomotives sat idling all day. I seem to have survived.

If a city has a local problem, they should take local measures. No point in crippling everybody to address a local problem.

The US has the the best air quality in living memory. Thus spracht the EPA. Even in LA, Tier II will not generate a reduction of 0.1 microgram per cubic meter of PM2.5. Out here on the frozen steppes where PM2.5 is below threshold of detection, this is all pain and no gain.

So some people say that infinitesimal benefits in air quality for the benefit of a very small subset of the population outweigh a large improvement in MPG for everybody. That makes improved MPG Mission: Impossible unless you force people to drive small cars they don't want.