Once this exists, it will just be a matter of time until it becomes mandatory. This is a guaranteed fact.
Public Safety, of course. Terrorists, child molesters, hate speech.
We'll have to be protected.
Really, this script writes itself.
Don't let the fear and negative thoughts cloud your head constantly and ask yourself how you can be positive and productive, without polluting the conversation with baseless doom and gloom statements.
We could easily provide half a dozen other major government initiatives which intersect with commercial activity and do not seem remotely on track to mandatory usage.
What makes this particular initiative different? If the postal service were created today, would you also suspect that it would become mandatory in a matter of time?
Edit - And furthermore, it's a govt issued id to track all your online transactions. This is tax revenue waiting to happen.
Read about it here: http://www.lysanderspooner.org/STAMP3.htm
Spooner's post office was so good that no one was really using the USPS any more. He was literally running them out of business.
That is, until Congress came in and said that what he was doing was illegal. Since then, there have been no alternative post offices.
Businesses like UPS and FedEx survive because of a loophole in the law that basically allows for parcel, but not post, shipping: http://mises.org/daily/3646
That said, they recently had a big regulatory battle between UPS and FedEx. I forget the specifics, but one business was being classified differently, and thus incurring higher operating costs than the other, simply because it was classified differently... In other words - punitive tax legislation. I forget exactly what happened there, and can't find a link at the moment buuuut:
The point is this: Your example of the post office is fundamentally flawed because it doesn't take into account that the post office is protected from market forces by legislation and thus, force.
The kind of regulatory problems ("classified differently") you describe are unfortunate, but those affect all major industries and are not specifically relevant to whether using the postal service is being protected. In other words, either UPS or FedEx having regulatory advantages doesn't mean that the overall tax/regulation regime is constructed so as to give the Postal Service a market advantage.
edit: see protomyth's comment; the Postal Service is unionized, so if anything FedEx seems to have the market advantage here.
As soon as "approved id" exist, the liability for allowing comments "without approved id" will skyrocket.