The tendency to split into competing groups with conflicting loyalties, or the state of being divided by internal groups pursuing separate interests.
From factional + -ism (suffix forming doctrines/systems). Became prominent in political discourse from the 18th century onward, especially describing internal party conflicts.
Founders like James Madison feared factionalism so much they designed the Constitution to prevent any single faction from controlling government — though it's still a constant political problem.
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