Well, 2024 is too early for alien contact...Unless they change it and have some evil aliens. 2024 is also..oh look, that is when the Bell riots that "made the Federation"(From DS9: Past Tense).
But it has to be Picards fault somehow......so maybe Picard spooked Sammuel Clemins back in the 19th century to write "All Aliens are Evil and Kill them All!" Maybe someone in 2024 found Data's head?
2024 should be close to the start of Treks World War Three...humm, I've heard a lot of talk lately of World War Three.
Oh..oh...oh.....maybe it's the evil worm bug aliens from TNG Conspiracy!