The motto "54, 40 or fight" is most useful in establishing the territorial expansion was driven by the desire to spread slavery.
The policy of broadening a nation's territory and its sphere of influence often at the expense of many other nations. Regional Add to list Portion. If your dog barks so when someone walks and via your yard, maybe because she's protective, or inclined to defend her territory from intruders.
The idea propelled 19th-century U.S. territory expansion when it was used to justify their forcible relocation of Native Americans or other communities from their homes. The quick westward expansion amplified the question of slavery as individual territories were added to a Union.
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