Let us be clear, Mrs Merkel is not defending diesel per se but the whole of German industry that refers to it.
Although she was able, with the stroke of a pen, to force E.on and RWE to phase out their nuclear power stations, she cannot oppose Mercedes-Benz, Volskwagen-Audi, BMW etc. without leaving a few political feathers in their mouths. Especially in the middle of an election period.
Diesel seems doomed in the long run, whatever technology is developed to filter the fine particles it emits. This condemnation is final, without appeal like all these condemnations formulated in the name of ecological morality, but what about the economic repercussions?
They are essentially of three types: loss of value for the owners of diesel vehicles, conversion costs for the refining industry (which is losing money in France), conversion costs for the automobile and related industries. If we only consider the public health aspects and ban diesel once and for all, we cannot complain about rising unemployment.
The right attitude would be to set a reasonable date for the end of diesel, to draw all the economic and industrial consequences from this and to see what accompanying measures can prepare both users and manufacturers for it.