Inside the NSA: How Do They Spy?

s. 1, ép. 2: The tightly guarded NSA Headquarters in Maryland covers more than 325 acres and has more than 30,000 employees with a vast number of buildings. They have a small army to protect them from foreign and domestic enemies, as well as their own fire department and swat team. Yet despite the large amount of space it occupies, the NSA had been created in secret and designed to be invisible.