Well don't you think it even just a bit ridiculous that he is involved in every single historical event through the 50's-the 80's? and to add onto that.. There is no way that Forrest Gump ran that far in his life with no money or anything. I also believe that even during vietnam they didn't hire mentally retarded people to fight in combat..
For me the film is so well put together that the ridicule of him being involved in historical events and achievements doesnt bother me that much...