Riots! Dark forces! Terrorism! American gangsters! The allegations are propaganda smears threatened dictators routinely employ to tar opponents and shift blame. Nazi Germany, the Soviet Union and communist China frequently slandered the U.S. as a gangster state. The Nazis and communists used 1930s Hollywood gangster flicks as visual evidence. In 2019, communist China's propagandists are using these bogus accusations as narrative warfare tropes to discredit Hong Kong's relentless pro-democracy demonstrations and -- potentially -- as reasons to suppress them militarily. Even gangsters. A pro-Beijing newspaper has claimed an American "black hand" is behind the protests, a term with terrorist and...