The doctrine that allowed people living in the territories to decide the issue of slavery through their governmental bodies was called popular sovereignty.
War used to be a grand thing before WW1 when it was considered honorable for men to go out and fight for their country. Even today, it still inspires a sense of nationalism and pride for one's country, though less now than before.
-communism spread
-millions died because of conflict and starvation
-people lost their freedoms and were uneducated.
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The answer is c blue lines to indicate the major rivers and lakes