[AFreeBird]

As for physically tracking its bearer, it could only do that either (a) when presented for access to government facilities or (b) when presented for travel.

Well, Smartcards use induction from the reader to power the card. Most readers use low power and requires close proximity to charge and then read the card. One could assume that increasing the power and upping the sensitivity of the reader would enable the gubmint to trigger and read the card from a greater distance, much the same process that toll roads are starting to employ.

Personally, if I get a gubmint issued national ID smartcard; the first thing I'm gonna do with it is give it a few seconds in a microwave.

[Poohbah]

Well, Smartcards use induction from the reader to power the card. Most readers use low power and requires close proximity to charge and then read the card. One could assume that increasing the power and upping the sensitivity of the reader would enable the gubmint to trigger and read the card from a greater distance, much the same process that toll roads are starting to employ.

The problem is that the propagation characteristics of the signal are downright lousy. IIRC, it's in a frequency band that gets absorbed by water vapor.