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Phoenix police officers stand beside a dump truck blocking a road outside the Phoenix Convention Center on Aug. 22. Protests were held against President Trump as he planned to host a rally inside the convention center. Matt York/AP hide caption

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Matt York/AP

Occupy Oakland protesters set trash on fire to make a barricade as police officers form a line to disperse them on Nov. 3., in Oakland, Calif. Kimihiro Hoshino/AFP/Getty Images hide caption

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Kimihiro Hoshino/AFP/Getty Images