What is RFID?
A Radio Frequency IDentification chip is a tiny, flat microchip with a built-in antenna. Although they come in many shapes and sizes, they all respond in the same way: when a radio signal is sent out to the chip, the RFID is activated and broadcasts the information it contains.
Think of an RFID chip as an electronic version of the children's game Marco Polo. When the RFID reader broadcasts 'Marco', the RFID chip replies 'Polo'.
RFID is used by many manufacturers to track their supply chain, making sure that shipment 'A' gets to retailer 'B'. Problems with RFID begin when the chips are used to track individual items, like clothing or passports. Few of us want to live in a 'Minority Report'-like world where the RFID chips in our clothing broadcast when and where we bought them.
The RFID chip the US State Department wants to put in our passports holds 64kb of information, five and a half times the amount of read-only data the Apollo 11 computer needed to put a man on the moon. This chip will contain all of the information currently on your US passport, including your photograph. None of this information will be encrypted. When an RFID reader says 'Marco' to the passport chip, the chip will broadcast the entire contents of your passport in a digital, copy-able format. The more power the reader sends out to the chip, the further away the chip can be read. An RFID reader modified by terrorists to send out a lot of power could be used, for example, to do a drive-by scan of cafes in order to determine which one had the most Americans in it.
A few thousand dollars and a little technical know-how is all it takes to buy and modify an RFID reader, a trifling sum for professional kidnappers, organized crime, or terrorist groups.
One of the State Department's own RFID subcontractors has criticized the scheme, stating the RFID plan "disregards a basic privacy approach and leaves out the basic security methods we would have expected to have been incorporated for the security of the documents".
Americans have enough things to worry about when traveling overseas: having an electronic bulls-eye on our backs shouldn't be one of them.