Originally Posted by
simpleSnow
Ah interesting, I never dealt with ESTA, but I do recall such warning messages. I would assume for either ESTA or ETIAS it doesn't give you your boarding pass unless you verify some sort of confirmation number.
No, that is not the case. For a flight to the US, it is possible to get your BP without an ESTA. But when you arrive at the gate you may be refused boarding if you do not have an ESTA or proof of US citizenship.