It is understandable that we should look for others to side with us when we have a just grievance and crave to retaliate against those who wronged us. The puzzling thing is that when our hatred does not spring from a visible grievance and does not seem justified, the desire for allies becomes more pressing. It is chiefly the unreasonable hatreds that drive us to merge with those who hate as we do, and it is this kind of hatred that serves as one of the most effective cementing agents.

Eric Hoffer (1902–1983) American writer, philosopher, longshoreman

True Believer: Thoughts on the Nature of Mass Movements, Part 3, ch. 14, § 68 (3.14.68) (1951)
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