It is now, but only because they were run out of northern Colorado & most of Wyoming several hundred years ago.
They also found less than enthusiastic welcomes in Nebraska & Kansas, while on their way to their present digs. Think NANA--No Apache Need Apply--as the policy of the tribes whose land they were invading moving through.
For that matter, the Lakota only possessed "their" sacred Black Hills around about 300 years ago, driving out other tribes when they pushed west, out of Minnesota. Believe me, they did not use a reputable Realtor for the transaction, nor even offer "$24 worth of beeds" for their new "ancestral home".
First, these "Native Americans" INVADED North America, pushing out, destroying, or otherwise supplanting the previous cultures. After that, they milled around fighting (and sometimes eating) each other incessantly for new places to live, until the white man found them.