Borderline Gringo — Tony Masero

Not many years before Ben Cade had been fighting with Teddy Roosevelt's ‘Rough Riders' in the Cuba campaign. Now he is back in Texas doing what he does best, riding cattle for Mister Delaware's Double-D spread.
He's happy enough until an intriguing telegraph message calls him away from the range and takes him to meet the enigmatic State Revenue Agent in Austin. But Bill McDonald is not all he appears to be and Ben is soon on a mission of mercy that takes him over the border heading for the small village of Tecozotlan.
Trouble is that that the situation below the Rio Grande is unstable. Revolution is rife and Ben finds himself in a land where disorder is the rule and the way is strewn with violent and bloody examples of this exploding turmoil.
Initially unwilling to take part, Ben is drawn in against his will and finds himself participating in a desperate battle against one of the cruelest and most bestial rulers of the country's chaos.