Answer:
Malcolm X promoted a separation policy as the answer to the race problem in the United States. Having total separation of blacks and whites played an important role in fighting racial discrimination. This was a defensive policy which looked to avoid conflict in US.
Explanation:
The Rocky mountains provided the greatest obstacle to railroad expansion
That phrase works perfectly! Although if you’d prefer a phrase that rhymes, Join the war and fight off shore might work (idk)
Otherwise, this works perfectly with your poster and would help express the symbolism you’ve provided!
Good luck and your poster looks rest so far!