What if The Comache led a guerilla war in America?
The POD would probably be during the Epidemic of 1816-17. Although a larger population does not necessarily mean a better military, for these purposes, it is a military advantage.
January 8, 1875
The President, Ulysses S Grant, had sent Paul Sheridan to New Orleans to negotiate the revolts and coups occurring in Louisiana. He lay back in his chair, as a box was handed to him. The man said it was from Sheridan, reporting on how horribly the conference went, with some New Orleans trinkets he thought the president might enjoy.
Ulysses opens the box, which explodes with a bright flash.
When Benjamin H. Bristow arrived moments later, Ulysses S. Grant was dead. His lower jaw and nose were missing and his face was charred. His right hand had vanished aswell. The President died instantly. The Windows of the Oval Office were cracked.
Further investigations revealed this was the work of Quanah Parker, the cheif of the Comanche.