We are made to believe that diesels are this, that and the other, but I'm sure it doesn't take a genius to work out that a lot of people use them, and there's a reason for that.
I learned to drive in a diesel, and my first car was a 1.2 petrol. I hated the petrol engine, it just didn't feel right for me. So, I've had diesels ever since and wouldn't choose to buy a petrol again.
Whilst diesel may be more polluting than petrol litre-for-litre, the economy on a diesel engine is much better, especially when the diesel cars are being driven as designed and are well maintained.
My missus has a petrol 1.4 Fiesta, and she buys as much fuel as me in a week, but travels half as much as me in my Megane 1.5dci. The Megane does 41.8mpg around town on average. I doubt the Fiesta does 30mpg.
I think if penalising diesel drivers is going to happen, it needs to be penalties on the drivers who use their big-engine diesels to drive half a mile down the road to pick up the kids after school or some other daft little journey like picking politicians up from a tube station in a Jag and taking them to Westminster 5 minutes away.
I don't think they'll ban diesel personal vehicles, because many people rely on them and gain from the benefits of a diesel engine.