Here's why:
* Prohibition: The 18th Amendment, enacted in 1919, prohibited the manufacture, sale, and transportation of alcoholic beverages. This created a huge black market for alcohol, which fueled the growth of organized crime syndicates.
* Bootlegging: Gangsters like Al Capone, Lucky Luciano, and Meyer Lansky established massive bootlegging operations, controlling production, distribution, and sale of illegal liquor.
* Gangland Violence: Competition for control of the lucrative bootlegging market led to brutal turf wars between rival gangs, resulting in numerous murders, shootings, and bombings.
* Publicity: The high-profile crimes, trials, and public figures associated with organized crime during Prohibition captivated the public imagination and made headlines.
While other examples of lawlessness existed in the 1920s, such as the rise of the Ku Klux Klan and the labor unrest in industries like coal mining, the widespread and organized nature of the bootlegging industry and the associated violence make it the most spectacular example.