Why would the Gov't go after 'hostile' Natives that were never hostile?  Who were nice enough to help Lewis and Clark out of the mountains and to the Columbia,  AKA ,their most desperate part of the trip.  And helped fight other tribes for the Gov't too.  Well of course some honkies wanted a high valley in the Wallowa country that belonged to the Nez Perce.   Chief Joe and the Nez Perce were now pissed off.  Then Chief Joseph took the U.S. Army on a 1200 mile wild ass goose chase.  Hot pursuit, hot pursuit!