Tread - Documentary of Killdozer guy

Docu-drama of Marvin Heermeyer, the guy who snapped & wrecked a town with a modified bulldozer in Colorado in 2004.
After welding himself inside the thing Marvin went on a rampage through town destroying whatever he wanted. When his bulldozer broke down, Marvin shot himself in the head w/ a 357 magnum.

A religious man, Heermeyer had a strong moral sense of good & evil which eventually led to his reaction.