[dropcap]I[/dropcap]n the running war with Mexican bandits, six U.S. Army cavalrymen fought a brief battle with hit-and-run raiders on Aug. 10, 1915 twenty-five miles on the Texas side of the Rio Grande.

It was only a matter of time before the violent convulsions wracking Mexico would spill over the border.  In the summer of 1915, halfway through the revolution that eventually took two million lives and drove hundreds of thousands into exile, Texans living in the Valley suddenly became targets i...