English Dopers!

So, Mayor Guiliani was knighted, but the AP reported that he cannot rightly be called “Sir Rudolph”, but why?. Also, it said that over 200 “Britons” were killed in the 9/11 attack. I thought that the term Briton is considered archaic. Just asking, but whenever I hear the word Briton, it is usually used to refer to a British person in the Dark Ages. Plz inform me!
Thanks,

Duplicate thread. See http://boards.straightdope.com/sdmb/showthread.php?threadid=93294