Yes, this is why the mayor of Pittsburgh made a big public pushback on Trump's "Pittsburgh, not Paris" speech -- Pittsburgh is an example of a city that recogni

Yes, this is why the mayor of Pittsburgh made a big public pushback on Trump's "Pittsburgh, not Paris" speech -- Pittsburgh is an example of a city that recognized the importance of breathing quality air and so was able to clean itself up from Beijing-level air quality to the modern-day green city it is today. Short YouTube video: https://youtu.be/tbFJMgfMCAs?t=1m12s https://youtu.be/tbFJMgfMCAs?t=1m12s