Yes , it's fictional , but it could be written if ALTAR Interactive continue to make UFO games that does not do the original justice.
You are not the only one that do not like the UFO:A games. If you're looking for a game with a similar experience to the orginal UFO games try the Fallout series , the Jagged Alliance games and Silent Storm and Silent Storm Sentinels (the Silent Storm Gold package contains both).
Hammer & Sickle though based on the Silent Storm engine is frustatingly hard and quite confusing.. I suggest you pass it over.