For the first time in recorded history, Earth has suffered a direct attack from an extra-teresstrial. They appeared out of nowhere, wielding massive anti-planetary weapons, effectively erasing the entire western Hemisphere before a counter-attack could be mounted. All in all, the death toll exceeded 3 billion, and almost all non-human life was extinguished due to the massive disruption of weather patterns in following decades. It would take almost a century for life on earth to return to 'business as usual'
However, even in the face of such grim circumstances, humanity still manages to survive. The attack was repelled before further damage to Earth, the moon, or any of the Mars Cities occurred, and within weeks, the remaining researchers on Human colonies began to focus their efforts on how exactly They managed to slip into the solar system undetected.
That's all the backstory I'm going to give you, I'm too lazy, and not liking the way my writing is turning out. Oh well. New thread. Long story short, Earth gets raped, war ensues.
