The Lieber code or has to do with martial law and military justice during wartime. What does that have to do with a poem?
Not talking about a poem, talking about freedom of speech and the Constitution. If you think the Lieber Code doesn't still apply read clause 2 and tell me where there was a repeal or peace treaty. Then read clauses 31-38 and tell me if things start sounding familiar. Then read The Hague Treaty of 1907 parts 43 and 55, that'll give you the court system.