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{{B}}American civil war{{/B}}
Historians of
the war can be divided into two schools. The first considers that it was the
unavoidable outcome of conflicting {{U}}(51) {{/U}} between Northern and
Southern {{U}}(52) {{/U}}. The second blames it {{U}}(53) {{/U}}
political leaders for {{U}}(54) {{/U}} to avert an unnecessary
war.
Analysts are also divided on whether the issue of slavery
was the primary cause of the war, or a symptom of other, more {{U}}(55)
{{/U}} differences—especially sectional interests and the doctrine of
states' rights—between the North and South which had been developing since the
formation of the American republic.
The fundamental
{{U}}(56) {{/U}} was economic. In the early 1840s the Northern states
began the process of industrialization, modernizing their society to meet the
demands of economic change. In {{U}}(57) {{/U}}, the slogan of Abraham
Lincoln's Republican party, "free labour, free land, free man" encapsulated the
ideology of valuing the freedom of individuals to grasp the {{U}}(58)
{{/U}} for economic self-advancement in a booming, expanding
society.
The Southern states remained stubbornly {{U}}(59)
{{/U}} both economically and socially. It was a backward-looking way of life
of tall white mansions on great {{U}}(60) {{/U}} dependent on a labour
system which made slaves of approximately 4 million black Americans.
America was {{U}}(61) {{/U}} divided by economic structure, and
was led into fratricidal(杀同胞的) warfare by a series of political clashes. The
most common cause was the future of the West. The crises over California's
admission in 1850 and over Kansas-Nebraska in 1854 were {{U}}(62) {{/U}}
of the divergent economic interests of North and South in relation to the
West.
The North wanted free land for independent labour in the
same new territories where the South {{U}}(63) {{/U}} to perpetuate its
traditional way of life by extending slavery. The issue was not the slavery
already practised, but the {{U}}(64) {{/U}} of its extension
{{U}}(65) {{/U}} the West.