Anyway haven’t passports been required to return from Canada … since about 9/11/01?
Actually, not really – I got back into the States from Canada as recently as October, 2008 with just my driver’s license and birth certificate. It was shortly after that when the passport became required. And I think you can still get between US & CAN with a NEXUS card (https://help.cbp.gov/app/answers/detail/a_id/227/kw/nexus%20card / http://www.cbp.gov/xp/cgov/travel/trusted_traveler/nexus_prog/nexus.xml).