To be fair, there really was some major scare of flying back in 2001 after the attacks, I remember it... But Britney still took DWAD to Japan. And it was not like it would be her first time touring many different countries, the OIDIA Tour was already international...
Anyway, to some extent, she wanted a break and thus DWAD did not extend throughout 2002, though she right after started working on In The Zone.
+ she was so fed up by the last show of DWAD.. you could tell
, 600K is too high though. 570K at most.
