"The embassies were full," said a former CIA official involved in deployment decisions. "We were losing officers by the dozens because we didn't have slots for them overseas."
In separate interviews, two former CIA case officers who joined the agency after the attacks said that 15% to 20% of their classmates had quit within a few years. Among them, they said, was one who had earned his master's degree in business administration from Harvard University and was fluent in Chinese and another who had left a high-paying job at the investment firm Goldman Sachs.
The front companies were created between 2002 and 2004, officials said, and most were set up to look like consulting firms or other businesses designed to be deliberately bland enough to escape attention.
About half were set up in Europe, officials said -- in part to put the agency in better position to track radical Muslim groups there, but also because of the ease of travel and comfortable living conditions. That consideration vexed some CIA veterans.
"How do you let someone have a white-collar lifestyle and be part of the blue-collar terrorist infrastructure?" said one high-ranking official who was critical of the program.
But the plan was to use the companies solely as bases. Case officers were forbidden from conducting operations in the country where their company was located. Instead, they were expected to adopt second and sometimes third aliases before traveling to their targets. The companies, known as platforms, would then remain intact to serve as vessels for the next crop of case officers who would have different targets.
'A very bitter fight'
The concept triggered fierce debate within the agency, officials said.
"This was a very bitter fight," said a CIA official who was a proponent of the plan because it insulated the fictitious firms from the actual work of espionage.
"When you link the cover to the operation, the minute the operation starts getting dicey, you run across the screen of the local police, the local [intelligence service] or even the senior people in the mosque," the official said. "I saw this kill these platforms repeatedly. The CIA invests millions of dollars and then something goes wrong and it's gone."
But critics called the arrangement convoluted, and argued that whatever energy the agency was devoting to the creation of covers should be focused on platforms that could get U.S. spies close to their most important targets.