Trope = Overused plot device
A trope is a convention. It can be a plot trick, a setup, a narrative structure, a character type, a linguistic idiom… you know it when you see it. Tropes are not inherently disruptive to a story; however, when the trope itself becomes intrusive, distracting the viewer rather than serving as shorthand, it has become a cliché.
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How racist tropes inform the present – From noble savage to helpless victims locked in unending tragedy, racist tropes from the colonial archive persist today and are invoked in contemporary politics.