Final answer:
Violent strikes affected labor unions' reputations negatively by reinforcing the perception that unions were associated with violence and unrest.
Step-by-step explanation:
Violent strikes had a negative impact on labor unions' reputations. These strikes often led to public perception of unions as radical and un-American, reinforcing the belief that unions were associated with violence and unrest. Examples such as the Homestead Steel Strike of 1892 and the Pullman Strike of 1894 left public opinion of labor strikes lower than ever and contributed to the decline of the labor movement for the next forty years.