Originally Posted by
dbuckho
How would one even board an international flight to the US/LAX without a passport to be at immigration in the first place?
I go through there pretty regularly - the choices are visitors or U.S. nationals and citizens like everywhere else.
Originally Posted by
Section 107
Echoing what DBuckho said - it is unlikely one would be boarded without a passport. However, there are documents other than passports that are acceptable for travel to the US. In the very rare cases where someone has one of those documents and not (also) a passport, those folks are DEFINITELY going to through secondary inspection and could use the diplomats/crew line. Perhaps (however unlikely) that is what your conversation partner was referencing...?
A green card holder technically only needs the plastic card to enter the US. However, airlines will give you a hard time boarding and CBP often asks for the passport as well.