I do get the basis for doing this to *uninsured* vehicles, since third parties should not be asked to assume risk for my actions on the road. I also get the basis for enforcing a yearly 'fit for purpose' test on my vehicle, since bald tyres, faulty brakes, and broken lights ought to be fixed within a year by responsible individuals. However, I can't see how the so-called vehicle tax fits into this category, other than being another way of robbing people and reminding them of their subjugation to the system that they, for the most part, have to depend on.
It stinks.