Final answer:
Southern Democrats during Reconstruction erroneously dismissed black politicians as unqualified, which was a misguided attempt to justify their own efforts to suppress African American political participation and restore the pre-Civil War social order, ultimately succeeding in disenfranchising black voters well into the 20th century.
Step-by-step explanation:
During Reconstruction, Southern Democrats' dismissal of black politicians as ignorant field hands was misguided because it underestimated the diverse backgrounds and capabilities of black politicians, many of whom were well-educated and capable leaders. The Resistance to black political participation by Democrats through violence and voting law 'reforms' led to the marginalization of black voices in the South for several generations. The negative stereotyping of black politicians by Democrats was not only an expression of racial prejudice but also a political strategy to maintain control and suppress the progress of African Americans in the political arena.
White Southerners, aligned with the Southern Democratic Party, displayed great resentment towards the social changes brought about by Reconstruction, with black individuals serving in positions of authority. This animosity fueled 'redeemer' movements and the establishment of laws and violence that sought to 'redeem' Southern states from the perceived misrule and return them to antebellum social dynamics. By the end of Reconstruction in 1877 and the subsequent rise in power of the Democrats, the dream of a racially equal and reconstructed South had been significantly undermined, laying the foundation for racial segregation and disenfranchisement that would last for decades to come.