Honorary US citizenship

One of the secondary plot lines in this movie involves one of the minor characters suddenly discovering he was an honorary citizen of the US because he was a direct descendant of Lafayette.

No doubt one of those plot devices used to move the movie along, but I decided to see if it had any basis in reality.

Apparently Maryland granted honorary state citizenship to Lafayette and his direct male descendants just before the US Constitution was ratified. It's not clear whether or not this gave them honorary citizenship in the US however. One of Lafayette's descendants, René de Chambrun, a famous French lawyer, did claim honorary US citizenship in 1932. Perhaps this was the basis for the movie plot line. Also, it became a minor news item in 1942 when it was questioned. Again, whether or not this gained publicity because of the 1941 movie I don't know.

It's also an open question of just what rights "honorary US citizenship" grants someone. You can't get a US passport because of honorary US citizenship, for example.