For a similar concept, the US offers a Passport Card, which is a Federal Photo ID card, that is legally considered a passport by domestic law, but other countri

For a similar concept, the US offers a Passport Card, which is a Federal Photo ID card, that is legally considered a passport by domestic law, but other countries may disagree. It can be used to enter Canada, Mexico, The Caribbean, and Bermuda by land or sea. It is not valid for international flights. It is unclear why, as it is designed to meet the ICAO standards for ID card sized travel documents. My best guess is that it is not valid for International aviation to avoid the problems with people trying to travel with it to places that need to be able to stamp a passport. (It is pretty much the only such Federal Photo ID card available to the general public in the US.) Obviously the passport card differs from EU National ID cards, in that they are never required to be owned/carried domestically, and full blown passports are not needed