what if your other passport is from a country that is part of
the visa-waiver program for entry into the US?
If I was originally from Germany(as an example), my German
passport would get me into the US visa-free. Let's say that I
become a US citizen on July 1. Then I discover the very next
afternoon that I need to fly back to Germany for some sort of
emergency. Definitely no time to get a US passport at such
late hours, so I hop on that evening's flight from New York to
Frankfurt, using my German passport. Can I return to the US
with my German passport?
I'm guessing the answer is no... but what if I fly back from
Germany to a Canadian city, say, Montreal... then take the
train from Montreal back to New York City.... Will my US
naturalization certificate and US driver's license be enough
to get me across the land border between Canada and US?