It is part of the REAL ID act signed into law on May 11 2005

If your state hasn't implemented the law, it will sooner or later.

http://www.murthy.com/news/n_drilic.html

This law contains, among many other items, new provisions regarding drivers' licenses. This law provides that, as of May 11, 2008, three years after its passage, a federal agency may not accept, for any purpose, a U.S. driver's license or identification card that does not meet the driver's license and identification card provisions of the Real ID Act.
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