The game, Millennium Challenge 2002, was the largest such simulation ever held, involving 13,500 people. It began, key participants say, with the Americans confidently assuming that they could intercept enemy communications (...).
But the enemy didn't cooperate. It used motorcycle couriers instead of radio and electronic messages, and sent orders as code words inserted into the muezzins' call to prayer - and this went right by the American intelligence analysts.
- How We Won the War, Nicholas D. Kristof, NYTimes, 02/09/06