As displayed in the United States Holocaust Memorial Museum, after World War II, German Lutheran Pastor Martin Niemöller had a well known quote which he repeated numerous times, about the guilt he had over his lack of action and complicity during the rise of Nazism.
Now for the much needed history lesson.
Originally, the right to vote was actually not for all citizens but for white men only. It wasn't until after the Civil War in 1868 that the 14th Amendment was passed that granted African Americans all rights accorded any other US citizen.
As described in the official US Government Archives site regarding the 14th Amendment:
A major provision of the 14th Amendment was to grant citizenship to “All persons born or naturalized in the United States,” thereby granting citizenship to formerly enslaved people.
Another equally important provision was the statement that “nor shall any state deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.”
This would obviously include the right to Vote.
The 15th Amendment, approved by Congress in 1870, was required to clarify that right given the laws passed predominantly in Southern States, that were aimed at restricting that right given by the 14th Amendment. Specifically, the official US Government Archives web page describing the rationale for the 15th Amendment clearly says:
African Americans exercised the right to vote and held office in many Southern states through the 1880s, but in the early 1890s, steps were taken to ensure subsequent “white supremacy.” Literacy tests for the vote, “grandfather clauses” excluding from the franchise all whose ancestors had not voted in the 1860s, and other devices to disenfranchise African Americans were written into the laws of former Confederate states.As crazy as that sounds, it wasn't until the 19th amendment to the Constitution, passed by Congress in 1919 and ratified in 1920, that the right to vote was granted to women as follows:
The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of sex.The right of citizens of the United States, who are eighteen years of age or older, to vote shall not be denied or abridged by the United States or by any State on account of age.