Frank Belknap Long 
Mars is My Destination 

There was trouble brewing on Mars-bad trouble. Two giant industrial empires fought for control there, and their struggle imperilled the whole Mars colony. Civil war-atomic civil war second-could break out any second, leaving Earth’s only foothold in space a mass of radioactive rubble. One man was needed to take charge-one man who could act fast and decisively, brutally if he had to. Ralph Graham got the job. And then the people around him started to die… (Goodreads)