Federal Air Transportation Airport Security Service
Around 150 years or so ago, President Lincoln found it necessary to hire a private investigator named Alan Pinkerton for protection - marking the beginning of the Secret Service. Since that date, Federal police authority has grown in depth, scope, and to a large number of multi-letter agencies - CID, OSI, NIS, FBI, CIA, INS, IRS, DEA, BATF, etc. Recently, due in large part to the September 11th tragedy, we now we have the "Federal Air Transportation Airport Security Service."