Schneier vs. Brin

[lud at tpg.com.au]

jon louis mann said the following on 3/8/2008 5:33 PM:
I found myself disturbed that I'm attracted to the idea of carrying an 
MP3 recording device at all times, just in case I get stopped by law 
enforcement and want my own recording of the event.

Ray writes:
I felt the same myself the other day when we were stopped by the Border
Patrol near White Sands NM. We were rudely treated and harassed by an
officious officer because we did not have our passports with us. It had
never been mentioned to us that this was "a US Govt requirement". I
"insulted" him by proffering my new South Dakota driving license! "A
note has been made on your record that you have been informed that next
time you are liable to be arrested". Left a real sour taste in the
mouth. This is the first person we have come across in our first four
weeks traveling through the US who has been unfriendly. In general,
people have been fantastically helpful and friendly.

A question just comes to mind.Do US citizens need to carry ID? 

Regards, Ray. (who spent the day in the fabulous Carlsbad Caverns -
fantastic!)