Would you be OK with the government mandating a permanent tattoo or an RFID chip implanted in your body for "identification purposes" or "security purposes"?
Personally? No. Will it happen? Perhaps, but not anytime in the near future. Will it matter to me? Again, no, it probably won't. Why? Because, so many people will have a problem with it that an alternative method will have to be allowed.
Having said that, if there were a valid reason for a tracking device being implanted, then I probably would do so.
For example, I were a colonist on a tera-forming project that had been ordered to check out an "anomaly" and had subsequently brought back something that then killed the colony and the Marines needed to locate my dead body... I mean they could just nuke it from orbit, just to be sure... However, if they needed to find MY body, then yeah, I'd get the RFID implanted.