In the 1890s, growing frustration and resentment among the plains indians led to ? american indians embracing the concept of assimilation.
american indians joining the ghost dance movement
. hostilities between american indians and the colorado militia.
a new treaty between the federal government and tribal leaders.

c

explanation:

answer: ensure protection from communism

explanation:

the north atlantic treaty was largely dormant until the korean war initiated the establishment of nato to implement it, by means of an integrated military structure: this included the formation of supreme headquarters allied powers europe in 1951, which adopted the western union's military structures and plans.