The question was already asked whether a US citizen can return on a valid passport which expires within 6 months of returning.
A lot of people commented and answered to the effect of "of course you can, it's your country!" And logically it makes sense.
However, I know of a few people who tried returning to the states (pre-Covid 19) and had problems. I believe they told me that they were stopped in the airport (of their visiting country) and the airlines wouldn't let them fly since they wouldn't be allowed to enter the US after they land.
Looking around online, it seems there are various blogposts which describe different experiences.
But I can't find any direct, unambiguous documentation from the US government itself addressing this specific question. Everything being discussed is just logical assumptions or personal experiences.
Can anyone share a verified, official , unambiguous source about this? Thanks
Edit:
I want to add one other nuance to explain why I'm looking for this information.
I have a friend who lives abroad and was planning a trip to the state for 3 weeks. His passport was expiring the week after he would arrive. His plan had been to use his expiring (but valid) passport to land in the states, then apply for a new passport while in the US.
He was told not to do it by a few travel agents, who told him that the airlines wouldn't let him fly because he needs his current passport to be valid for 6 months from the time he was planning on leaving.
He was bothered by this- what did it matter that he was planning to leave in a few weeks? If he's a US citizen, he should be able to land regardless of his future flights. And for his return flight he'll have a new one already.
This is what started this discussion. That's why I want to see official US policy. Is a US citizen living abroad considered to be like a visitor, who needs 6 months (since there's a plan to return?) or is the only determinate that the passport is valid.