They were there against the civil right worker's murders. While the black population at the time was allowed to vote, in the Southern states they were withheld from voting by all sorts of idiotic reasons.
The preamble of the United States constituon serves the purpose of showing the intention of the writers and also the use and purpose of the document.
Black friday is your answer
Nazis built extermination camps equipped with huge gas chambers that could kill as many as 6000 human beings in a day. Those labeled as weak would die. They were told to undress for a shower and then led into a chamber with fake shower heads. After the doors were closed, cyanide gas poured from the shower heads. All inside were killed in a matter of minutes.
The development of agriculture was a hallmark for the development of human civilization. Before that, humans had to focus their efforts on hunting and harvesting for food, so the effort existed to sustain life. After the development of agriculture, civilizations came to have a food security, that is, subsistence is no longer a doubt. From then on, society can turn its attention to other activities and has experienced a major evolution. One of the activities by which people could develop was work, which eventually led to the development of technologies. The industrial revolution is the result of the human capacity to work and create technological tools. This was only possible after the population had a food security, thanks to the agriculture revolution.