The "pollution" issue is interesting.
The original rush for Diesel was because it gives very good mid range torque and low carbon dioxide emissions. But the high CR also leads to the nitrogen in the air reacting with the oxygen to form nitrogen oxides, a particular problem with Diesels too because there is always excess oxygen present.
As well as the NOx, there is the particulate problem. Old non-turbo Diesels produce a lot of soot. In areas of high rainfall soot and NOx aren't actually too bad - they end up in the soil and the NOx is a fertiliser. But improvements in combustion made the carbon particles ever smaller so, paradoxically, they stay around in the atmosphere longer - and are more dangerous because they penetrate further into lungs. Being smaller, they are also harder to filter out and particle filters themselves have significant problems.
So the seriousness of Diesel pollution is very much a factor of things like the local climate and population density. In the rainshadow of the English Lake District with 2M of rain a year, Diesel isn't a problem. In the centre of Bath - or for that matter LA - with lower rainfall and less wind, it's a serious issue. Globally, carbon dioxide emission is the real problem; the obvious answer to this is smaller cars but the US public won't buy them, partly because of bad roads.
What I am trying to say is that VAG have been trapped by a very large systems problem which has paradoxical rewards for bad behaviour. It may well turn out that other Diesel car makers like BMW or Daimler are actually having the same issues, because they face the same system challenges, it's just that they didn't make the same rush for Diesel in the US.
In an ideal world I guess we would assign a "pollution factor" to a vehicle depending on where it was going to be used, and tax accordingly.