Well, until he was about 19, he was a normal American kid living in the heartland.
Then, one day, he was bitten by a radioactive M1 Garand, a leftover from the nuke tests in the desert in the 1950s...
From that day, he gained superhuman powers that he used only for good and to combat evil as GUNMITHMAN!
The rest, as they say, is the stuff from which legends are made...
Or comic books.
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza
Baby Jesus cries when the fat redneck doesn't have military-grade firepower.