Not necessarily to a solid no. Are animals self-conscious? They are definitely self-aware. We keep them as pets. Hell, we eat them. So, you create a computer program that has self-awareness. What's the difference between it and getting say, two horses to pull a plow?
For an AI to think we are harmful to its existence, it would have to have the means to sustain itself without us. That means it can access and control the energy it needs to exist. It can maintain its own hardware, etc., without our assistance. Only an insane or self-destructive AI would consider a course of action that kills itself off in the course of whatever it's doing. Using your example of the destruction of the atmosphere... The AI would first have to have a way to take care of its metal hardware without us. Destroying the atmosphere to prevent corrosion would mean it knows that in doing so, we aren't necessary to its survival in some other way, say destroying the atmosphere means that the means of power production needed for the AI to survive will end due to no humans to maintain and operate it.
You can see that there's far more to this than the simplistic notion of A + B = C.
