Damn aliens - they have nothing better to do than attack the human race. Time to take control of a spaceship and wage your own war against these extraterrestrial roaches.
You'll fly a piece of space junk at first, but after a dozen or so successful missions you'll make enough cash for a hardcore battleship. Now it's up to you to put together a bold team and equip your ship the best lasers, blasters, missiles, and whatnot available on the black market. The aliens will regret ever messing with Earth!