Soccer fields are usually full of uniformed children chasing a diamond patterned ball around a manicured lawn on a Saturday morning.

Parents are normally scattered down the sidelines in fold-up camping chairs, churning out laughter and giving high-fives.

It shouldn’t be a battlefield. But sometimes it is, as one Texarkana, Ark., Police Department detective has seen.

John David Cowart, a major in the Marine Corps, returned home to Texarkana in April from Iraq where he served as commanding officer of India Company, 3rd Battalion, 23rd Marines.

Wh...