The United States and other governments have reflexively made identity documents a focus of post-9/11 security efforts. ID systems are significant because they have the potential to enable the mass tracking and surveillance of individuals.
The United States is pushing for the international adoption of a "globally interoperable" standard for passports that include biometrics and remotely readable radio tags (also known as RFID or "contactless" chips). That has enormous implications that reach far beyond passports, and amount to the first steps toward a global identity document, with all the consequences that would bring for our privacy.
Statewatch report -- Biometrics: The EU takes another step down the road to 1984 (Sept 19, 2003)
Statewatch report -- The road to 1984 - Part II: EU: Everyone will have to have their fingerprints taken to get a passport (Feb 26, 2004)
Open letter to the ICAO on biometric passports (March 30, 2004)
Privacy International letter to the European Parliament on biometric passports (Oct 25, 2004)
ACLU white paper on RFID passports (Nov 26, 2004)
State Department Documents on Passport Standards acquired by ACLU (Nov 26, 2004)
Statewatch report -- EU: biometric visa policy unworkable (Jan 5, 2005)
ACLU Comments to U.S. State Department on RFID Passports (April 4, 2005)