After the 9/11 attacks, every U.S. intelligence agency was mandated to have a Red Team -- an alternative analysis component -- so that people in the government could imagine the unthinkable. The CENTCOM unit was established in April 2006 following an order by then-Secretary of Defense Donald Rumsfeld, with a charter to provide the CENTCOM commander, leadership, and staff with alternative viewpoints, challenge common assumptions, and anticipate unintended consequences of events and actions.
And here's the article that is referred to.