How digital tech has changed espionage
Scientists working for U.S. intelligence have come up with some nifty ways to steal and communicate secrets over the years - from ball point pens that conceal tiny cameras to a freeze-dried rat with a hollow abdomen to hide information.
These days, of course, the spy game of covert communications is played out digitally, on computers, mobile phones, and the Internet.
Guest: H. Keith Melton, co-author of Spycraft: The Secret History of the CIA's Spytechs from Communism to Al Qaeda
