Odd situations occur. I remember the 2002 Winter Olympics in Utah when Australia took a couple of medals or so.
They wanted to hear Waltzing Matilda, but this was stopped because of U. S. copyrights on the melody usually used in Australia.
There is a thread on this somewhere in mudcat, I have forgotten the details.

There is nothing to prevent someone from outside the U. S. obtaining a U. S. copyright in addition; many do.