In light of this question and its answers and comments, I have a question.
I am a US expat living abroad for many years. On one visit to the US (NY state), I tried to pay in a store with a check (personal check, on a US bank where I still had an account). The cashier wanted, of course, a driver's license. I no longer had one. I tried to use my passport but she did not consider it valid id and would not allow me to pay by check (I don't remember how I paid :-) ).
The question I referred to relates to the issue of what to use for id when visiting the US:
She wants to keep it for Identification she needs for paperwork, etc when conferring with her US bank accounts, etc.
As someone who resides outside the US, she should use her passport as identification when visiting the US.
Apparently though, it does not always work. How can an expat use a personal check, when visiting the US? If it is the passport, is there somewhere this is documented? Something I could print out and show to a cashier who does not know?