Why did woodrow wilson order john j. pershing and his expeditionary force home

in 1897, pershing became a tactical officer at west point, and that's where he was given the nickname "black jack." pershing's first name is "john," for which "jack" is a nickname, and he was a white man who commanded black troops. hence "black jack".

where are the statements?

it proved indian land claims were unjustified.