near the midpoint of the Baltimore-Washington Parkway.

In the NSA's early years, the US government did not publicly acknowledge it. NSA stood for "no such agency," joked its employees.

That changed with the 1973-76 investigations of US intelligence abuses by Sen. Frank Church (D) of Idaho. The NSA had kept a "watch list" of US citizens and organizations whose foreign communications it intercepted, it turned out. The NSA had also kept copies of most telegrams sent from the United States to foreign countries.

The response to these revelations was the 1978 Foreign Intelligence Surveillance Act, or FISA - a law that set judicial procedures for requesting electronic surveillance of persons thought to be engaged in espionage or terrorism against the US.

Today the NSA is in the curious position of being bothsecretive and famous. Its work remains so closely held that its director seldom appears in public. Yet it has starred (as the villain) in at least one recent feature-length movie, "Enemy of the State." The NSA itself, perhaps to bolster its image, has created a website for children, which features the Cryptokids, an assortment of cartoon animal characters who, in games, carry out code-breaking assignments and other espionage activities.

Following the fall of the Berlin Wall, and the loss of the agency's cold-war mission of eavesdropping on everything from Soviet missile telemetry to the car-phone calls of Kremlin leaders, the NSA lost about one-third of its budget, and one-third of its manpower.

At the same time, in the decade of the 1990s the world saw an explosion in what NSA