Another Monday Morning

You travel to the year 1880. Once there, you hunt down Wyatt Earp, and then stalk him for three months. One night, he walks out to the outhouse. You run up to the outhouse while he's inside, open the door, and shoot him. You just killed Wyatt Earp while he was on the crapper. You find the time machine near a cave, and travel to your own time. You arrive back at what looks like the mall where you found the time machine, but it looks like it has been renovated into a gun store. It turns out that sometime in the early 20th century, Jesse James became president, having not been shot to death. He turned the country into a lawless society where the only hope for survival is to own a bunch of guns.