People began to colonize other planets and fight for them already. You find yourself in the event of one of these conflicts. You speak of the founder of the colony on the planet number 51. As on other planets there are constant war colonizers, and your is not an exception. We need in addition to the structure of the base, recruit and train soldiers, who will repel waves of attacks. If too many enemies will be your base, you'll lose and forced to leave the planet.