BLM has belatedly decided that Col. Lloyd Garrison was right, and since the Constitution countenanced slavery, it was a pact with the Devil, and since the free states failed to secede from the Union, they were all eeeeeevil!, too. So they are accepting the view of a white man against that of Frederick Douglas, a former slave, who believed that the Constitution and Declaration were incompatible with slavery, and that since the Constitution was drafted in order to make a more perfect union, it would in time reject slavery entirely in spite of the temporary allowances it made for the institution, and therefore every time a slave holder saluted the heroes of the Revolution, he doomed himself. History has proven Frederick Douglas right, but belatedly, BLM is listening to that honkey Garrison instead of the soul bro. Therefore, the Civil Rights Movement was simply too little, too late, and irrelevant. Whitey is evil. Paleface Lloyd Garrison said so.
Douglass had it right. The Declaration of Independence set out our ideals as a people — All men are created equal and have certain inalienable rights. We are also humans, and as such are imperfect. We have failed to live up to this ideal, more so at some times in our history than others. The Constitution was such an example. It contains language that recognized the political reality of the late 18th century. Unfortunately part of that reality was that slavery was legal in many states. In order to get the Constitution ratified, this was necessary. It does not mean the Constitution was pro slavery, though, just that the Founders has to bow to the practicalities of their time.