This is a “When I was a boy” post.
As I remember, it was in the 1960s when environmentalists began expressing concern about pollution from motorcars. The discussion focused on the the smog that was trapped by cold air inversion in the Los Angeles basin
in the days when Americans drove cars like this.
These were the days when Donella and Dennis Meadows had published Limits to Growth, a work that suggested that the earth was going to run out of resources.
Neither the idea that we to limit the size and use of our motorcars nor that we were going to run out of resources was particularly well received in the 1960s
Since then, things have changed in the motor car industry. Cars have become smaller, engine efficiencies have improved, unleaded fuel has been introduced. But pollution rates have increased simply because there are more motorcars on the road.
It has taken nearly 60 years for a viable technological alternative to emerge. The alternative still requires widespread solar power to be available for electric powered motorcars to run with zero pollution rates.
What this means is that it is going to be quite long time before things get better.