John, you appear to have missed some fundamentals of copyright and defamation law, although copyright of course is not relevant to material the copyright in which has expired - and copyright was at most in its formative period as a concept in the 1500s and possibly rather less.

More significantly in current terms, if a recording of a performance of a person (or composition of a person) is used to support a cause, it implies that that performer or composer supports that cause.

If that performer or composer has previously stated that he does not support that cause, then the use of the recording implies that the performer or composer is a liar.

The Republicans in the USA have I think felt impelled to settle legal proceedings brought there by Bruce Springsteen on (I understand) similar grounds.