官方解释：
Adult passengers 18 and over must show valid identification at the airport checkpoint in order to travel.We understand passengers occasionally arrive at the airport without an ID, because of losing it or inadvertently leaving it at home. If this happens to you, it does not necessarily mean you won't be allowed to fly. If you are willing to provide additional information, we have other ways to confirm your identity, like using publicly available databases, so you can reach your flight.If we clear you through this process, we may give you additional screening. If we can’t verify your identity, you may not be allowed to enter the screening checkpoint or to board a plane.Acceptable IDs for screening purposes include:U.S. passportU.S. passport cardDHS trusted traveler cards (Global Entry, NEXUS, SENTRI, FAST)U.S. military ID (active duty or retired military and their dependents, and DoD civilians)Permanent resident cardBorder crossing cardDHS-designated enhanced driver's licenseDriver's licenses or other state photo identity cards issued by Department of Motor Vehicles (or equivalent) for the sole purpose of identificationFederally recognized, tribal-issued photo IDHSPD-12 PIV cardAirline or airport-issued ID (if issued under a TSA-approved security plan)Foreign government-issued passportCanadian provincial driver's license or Indian and Northern Affairs Canada cardTransportation Worker Identification Credential Note: a weapon permit is not an acceptable form of identification.