You are not alone on the planet. Hundreds of pods have crashed on the planet and people are waiting to be saved. And you will need to keep them warm, fed and under a roof. Or they will get unhappy.
Manufacture and deploy marines to attack your foes and defend your colonists!
It's a mix of ColonialCharter and FoodIndustry. So you'll have colonists to feed and let them stay alive. Luckily they also work for you.