Counting the Cost, Hammer's Slammers Ser.
Paperback, 288 Pages, Baen Books, November 1987 
ISBN: 0671653555 

The hottest science fiction mercenaries of the decade are back, so why count the cost? The other guy is going to pay for it! Hammer's Slammers must win a two-front war while maintaining the civilian power structure against hordes of religious fanatics. Original.