Not wishing to trust Big Gov, but--
The UK is the only advanced country (apart from the US, I think) that does NOT have an ID card system.
Yesterday, a Belgian minister made the point that one reason illegal immigrants are so desperate to get to the UK from Belgium/France/wherever is that, without an ID card system the UK cannot track them, whereas other countries can.
Good grief, the Germans have one, and if there is any nation that is wary of over-reaching government powers it is surely them.
Within the UK, an ID card would dramatically simplify control of access to health, social security and other benefits.
Most of us already have a card - it's called a passport. It is simply not required to be presented for these purposes.
PLEASE let's have a central system and stop moaning.
I care much more about commercial entities tracking me. The government can be voted out, Google is harder.