Mike Resnick 
Starship: Rebel 

The date is 1968 of the Galactic Era, almost three thousand years from now. The Republic, dominated by the human race, is in the midst of an all-out war with the Teroni Federation. Almost a year has passed since the events of Starship: Mercenary. Captain Wilson Cole now commands a fleet of almost fifty ships, and he has become the single greatest military force on the Inner Frontier. With one exception. The Republic still comes and goes as it pleases, taking what it wants, conscripting men, and extorting taxes, even though the Frontier worlds receive nothing in exchange. And, of course, the government still wants Wilson Cole and the starship Theodore Roosevelt. He has no interest in confronting such an overwhelming force, and constantly steers clear of them. Then an incident occurs that changes everything, and Cole declares war on the Republic. Outnumbered and always outgunned, his fleet is no match for the Republics millions of military vessels, even after he forges alliances with the warlords he previously hunted down. Its a hopeless cause…but thats just what Wilson Cole and the Teddy R. are best at.