(CNN) Think your driver's license is enough to get you through airport security in the United States and onto your domestic flight?
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Some two-thirds of US state driver's licenses are not compliant with a post-9/11 security law set to go into affect on October 1. Those who are not compliant will not be able to fly if they don't have other forms of "REAL ID-compliant" identification.
Concerned about the impact on travel, the head of the US Department of Homeland Security loosened the restrictions this week, allowing the various state agencies to accept identity documents electronically.