As of May 2024, it has been almost 20 years since the 9/11 Commission recommended federal standards for identification, which resulted in the enactment of the controversial REAL ID Act in 2005. According to the 9/11 Commission's report on page 390:

At many entry points to vulnerable facilities, including gates for boarding aircraft, sources of identification are the last opportunity to ensure that people are who they say they are and to check whether they are terrorists.

On the other hand, opponents such as security expert Bruce Schneier have argued that REAL ID imposes significant costs for little benefit, as well as introducing new vulnerabilities. The Electronic Frontier Foundation has said that REAL ID:

. . . requires a vast national database linking all of the ID records together. Once the IDs and database are in place their uses will inevitably expand to facilitate a wide range of surveillance activities.

Full implementation of the law has been slow, with some states such as Maine, South Carolina and Pennsylvania refusing to comply. Originally set for May 11, 2008, full implementation of REAL ID was at first delayed to December 31, 2009 and then has had a series of delays after that. Finally on December 5, 2022, DHS announced the latest extension, of 24 months, for the 50 US states to bring their driver's licenses and ID cards into compliance with the Act.