Final answer:
The anti-cocaine sentiment in the 20th century was caused by factors such as the widespread use of cocaine, concerns about social degeneration, and the association of crack cocaine with addiction and crime. The harsh drug laws and sentencing disparities further contributed to the sentiment.
Step-by-step explanation:
The anti-cocaine sentiment in the 20th century was caused by various factors. In the early 1900s, cocaine was regarded as a medicinal pick-me-up and was used by respectable diners. However, as drug use spread, concerns about social degeneration and the negative effects of cocaine also increased. Novels critiquing the hypocrisy of social elites further contributed to the anti-cocaine sentiment. In the later decades of the 20th century, the introduction of crack cocaine and its association with addiction and violent crime led to harsher drug laws and sentencing disparities, which disproportionately affected lower-income communities.