Cover's Return Address Question

Trying to determine if this cover might be connected to a French sailor associated with a U.S. ship that was provided to France under a WWII lend/lease agreement. Towards the end of WWII a number of U.S. ships were provided to France resulting in a change of the ship's name (not always) and the designation of the ship (e.g. the U.S. designation DE-109 might become Fxxx while under French control).

The return address of "F102. c/o U.S.N. Liasi. Off/South Dry Dock Boston" and the French "Marine Nationale Censure" marking might lend some credibility to my theory.

Any input is appreciated.

Just a thought, U.S.M. Liais. Off. sounds like US Marines liaison officer, maybe US army needed people who speak french to coordinate with France. That could be the reason why it passed through France censure (marine nationale), they wanted to make sure the liaison officer don't send sensible information away... Just an hypothesis!

Thank you for responding. Based on the "N" in Boston I believe it is U.S.N. versus U.S.M.