In September 2007, the Inspector General of the Justice Department reported that the Terrorist Screening Center (the FBI-administered organization that consolidates terrorist watch list information in the United States) had over 700,000 names in its database as of April 2007 - and that the list was growing by an average of over 20,000 records per month.1 (See also this new March 2008 report.2 )
By those numbers, the list now has over one million names on it. Terrorist watch lists must be tightly focused on true terrorists who pose a genuine threat. Bloated lists are bad because
1) they ensnare many innocent travelers as suspected terrorists, and
2) because they waste screeners' time and divert their energies from looking for true terrorists.