WASHINGTON (Reuters) - As CIA Director Porter Goss tries to rebuild the agency's global operations, he faces a shortage of experienced spies created by a post-September 11 stampede to the private sector, current and former intelligence officials say. Goss, who a year ago inherited a CIA wracked by criticism of intelligence failures over Iraq and the September 11, 2001, attacks, has come under fire from critics about the publicized departures of several high-level clandestine officers. Reform advocates see the loss of senior officials as a natural consequence of changes intended to root out an old guard blamed for lapses that...