John,  I believe that U.S. copyright law now conforms closely to U.K.
and European copyright law.  Under the Copyright Act of 1909 the United
States pretty much went its own way and chose not adhere to the Berne
Copyright Convention when it was later enacted -- differing in such
provisions as copyright duration (28 years, plus an optional renewal
term of another 28 years), requirement for copyright notice (without
a printed notice on each copy, protection was forfeited), manufacturing
requirement (the protected items had to be manufactured in the U.S.,
although there was an "ad interim" provision for items manufactured
abroad), and in other details.

The Copyright Act of 1976 changed the duration to "life plus 50 years"
(or 75 years for anonymous or corporate creation), and it subsequently,
when we finally subscribed to the Berne Convention, abolished the
notice requirement.  These changes were an attempt to bring U.S.
practice into line with European practice.

Two other important features of the 1976 act were that it abolished
all distinction between common-law copyright and statutory copyright,
eliminating the necessity of registration as a requirement of copyright
protection (i.e., the mere act of creation gives you copyright protection
of the thing you have created); and secondly, it made explicit provision
for the copyrighting of sound recordings, which were not copyrightable
under the 1909 act.

I am not up on the more recent changes to the 1976 act.  But the late
Congressman Sonny Bono -- financed, they say, by Walt Disney Studios --
got legislation passed that played havoc with the finite-term concept
of U.S. copyright theory.  I believe we have extended the term to 70
years or more.  I know that 1922/1923 was the public domain/copyright
dividing line in the year Bono did his work, and that it was advancing
each year as time passed, so that 1922/1923 would in another year
become 1923/1924, and so on at every successive 365-day passage of
time.  But we are now frozen in the 1922/1923 state until (I think)
the year 2024, when the clock will start running again on copyright
expiration.

Don't ever say that money can't buy you time.

Matthew Caulfield (not a lawyer)
Irondequoit, New York