Rabble rouser

A demagogue /ˈdɛməɡɒɡ/ (from Greek δημαγωγός, a popular leader, a leader of a mob, from δῆμος, people, populace, the commons + ἀγωγός leading, leader) or rabble-rouser is a leader in a democracy who gains popularity by exploiting prejudice and ignorance among the common people, whipping up the passions of the crowd and shutting down reasoned deliberation. Demagogues overturn established customs of political conduct, or promise or threaten to do so.

Demagogues have appeared in democracies since ancient Athens. They exploit a fundamental weakness in democracy: because ultimate power is held by the people, it is possible for the people to give that power to someone who appeals to the lowest common denominator of a large segment of the population. Demagogues have usually advocated immediate, forceful action to address a national crisis while accusing moderate and thoughtful opponents of weakness or disloyalty.

The word demagogue, originally meaning a leader of the common people, was first coined in ancient Greece with no negative connotation, but eventually came to mean a troublesome kind of leader who occasionally arose in Athenian democracy. Even though democracy gave power to the common people, elections still tended to favor the aristocratic class, which favored deliberation and decorum. Demagogues were a new kind of leader who emerged from the lower classes. Demagogues relentlessly advocated action, usually violent—immediately and without deliberation. Demagogues appealed directly to the emotions of the poor and uninformed, pursuing power, telling lies to stir up hysteria, exploiting crises to intensify popular support for their calls to immediate action and increased authority, and accusing moderate opponents of weakness or disloyalty to the nation. While many politicians in a democracy make occasional small sacrifices of truth, subtlety, or long-term concerns to maintain popular support, demagogues do these things relentlessly and without self-restraint.

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Wikipedia