If the Borg are serious about assimilating Earth and can adapt to different situations then why didn't they realize that sending ONE cube to earth was a non starter? It is obvious they have thousands of cubes. If they were smart they would of sent 500 or more cubes to Earth, there is no way Starfleet could of fought them all off. I think the Borg needs to assimilate a race that knows how to conduct a battle.