The White House is considering expanding the power of a little-known Pentagon agency called the Counterintelligence Field Activity, or CIFA, which was created three years ago. The proposal, made by a presidential commission, would transform CIFA from an office that coordinates Pentagon security efforts—including protecting military facilities from attack—to one that also has authority to investigate crimes within the United States such as treason, foreign or terrorist sabotage or even economic espionage.