Source: AP/Je1ff Widener
The image of a defiant man stopping a column of Chinese Red Army tanks heading towards the 1989 Tiananmen Square massacre has become iconic. Two recently unearthed photos give greater context—the uncropped photo is frankly terrifying.
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UPDATE: Video here of the massacre and the confrontation, when for one moment the honour of one billion people rested on the shoulders of one man. [Hat tip Riko S.]