Answer:
The Shoshone tribe provided them with horses for their ascent over the Bitterroot mountains
Explanation:
If we are doing the same thing this is your answer.
The Americas are the big answer here. They held other holdings in other places as well.
The British defeated the French in Quebec. In 1760 the British took over Fort Pontchartrai
The people who would most likely support imperialism here would be capitalists and the media. Capitalists because they can produce much higher amounts of goods for a much lower price - exploiting the local population, and the media because they have stories to talk about which sell :)