Blue SunSet - Blue Sun Series, #2

The aliens just want us all to die. Two men and a Martian "Scout Bug" have other ideas. Earth is in political and economic turmoil in the wake of an unprovoked alien attack. NASA abandons the crew on Mars as power shifts to a reactionary political party, but they reconsider when new lights and radiation bloom on the periphery of our solar system. NASA needs Mars to once again act as the sacrificial lamb for the incoming missiles, but the Mars' crew has their own problems after one of the missiles strikes Mars and turns the environment from inhospitable to unlivable.
It seems their only choice is death by starvation, hypothermia or the next alien missile. Something on Mars awakens after millennia of stasis. It is hungry, and the human crew on the surface is obviously food, albeit genetically damaged food. The genetic damage will need to be corrected before the harvest. Astonishingly, the next round of incoming alien missiles begins communicating, and the Mars Crew learns that the galaxy has been subjected to a reign of genocidal bombardment for thousands of years.
They have suffered much, but the crew on Mars and the fully awake Martians decide to go down fighting.