Okay, I'm making an RTS, and it'll be a simple RTS. You have a mission, you control only one type of unit, and so does your enemy. You only have one objective, and so does your enemy. Now, the maps are reletively small, and I was wondering, what is a good algorithm for my AI? What processes should it go through to acheive it's goal?

The first mission you have to defend your bunker from the AI, who is attacking you. The goal is simple, the AI wants to kill you. The ai sends waves of troops in increasing number. What is a good algorithm here?