Summary

Various Encyclopaedia Britannica, 11th Edition…

Southern leaders generally were now beginning to perceive, as Calhoun had already seen, that there was a permanent conflict between the North and the South, not only a divergence of interests between manufacturing and agricultural sections, but an inevitable struggle between free and slave labour. Should enough free states be admitted into the Union to destroy the balance of power, the North would naturally gain a preponderance in the Senate, as it had in the House, and might, within constitutional limits, legislate as it pleased.
Source: Gutenberg

Various Encyclopaedia Britannica, 11th Edition…

With the murder of Othman the dynastic principle gained the twofold advantage of a legitimate cry—that of vengeance for the blood of the grey-haired caliph and a distinguished champion, the governor Moawiya, whose position in Syria was impregnable. The kernel of his subjects consisted of genuine Arabs, not only recent immigrants along with Islam, but also old settlers who, through contact with the Roman empire and the Christian church, had become to some extent civilized.
Source: Gutenberg

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