Originally Posted by
poisson
Are you still required to speak to an agent after using one of these machines?
Yes, but at many airports, if you get a non-X receipt, that officer will be at a basic stand rather than a fully-equipped booth, and is increasingly unlikely to stamp (esp. US) passports.
Fully automated processing (eg gates) like in Europe would only be possible to implement for US citizens and permanent residents, since only they have an absolute right (disputable in the case of LPR:s, but usually they do) to enter the US without being questioned. Granted, Global Entry does work for a subset of foreigners, however they undergo background checks as part of the enrolment process, and membership can be revoked at any time the CBP deems fit.
Granted, Australia and New Zealand offers fully automated processing for a subset of foreigners, but those countries' border procedures aren't as strict as in the US
Originally Posted by
televisor
Yes. They don't admit you into the US, they only let you deal with the declaration (and possibly data entry in some cases).
Declaration, facial image, fingerprints, passport/green card/visa scan, and background checks