Human groups cannot coexist because they are headed in different directions, whether ethnic, cultural, religious, racial, or political. Democrats now realize they cannot coexist with us, and we cannot have one leader for both factions. The USA is a dead letter, as is the EU for the same reason.
Most people have trouble separating cause and effect because it requires diligence, analysis, and creativity to understand that a cause is separate from related events. For example, a proposed plan may have disadvantages, but the causal question is whether or not it achieves what it intends to achieve.
In the same way, people have trouble understanding historical causes versus pretexts, touchstones, and political justifications for war. Many still think that the Civil War was about slavery, when in fact it centered on the issue of autonomy for the states.
The North wanted to capture the Southern economies because, as producers of cotton, the South was charging high prices for the raw materials the North required to make into textiles. Vertical integration, or ownership of those Southern farms, would make more money for the North, whose economy was otherwise becoming unstable.
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