Every human being is a desendent of slaves. America did not invent slavery, nor was it the first to end it. But it was among the first. Great Britain abolished slavery in the British Empire in 1807. The United States took another another 55 years. Before Spain, Portugal, Egypt and many other had done so. White people ENDED slavery.
...except for the parts of the world where it is still practiced.
Slavery in the U.S. was basically a relic of the British Empire. They may have banned it in their own country 55 years earlier than here, but only because it wasn’t so invested there. The newly formed U.S. government just didn’t have the power to ban slavery at that time, because the British had so institutionalized it. It finally took a civil war, and the bloodiest one in our history. I’ve heard some say that the Civil War wasn’t about slavery. But without the issue of slavery in the first place, the Civil War would not have happened.
The British outlawed the slave TRADE in 1807. This just about coincided with the abolition of the slave trade in the US constitution (20 years after the constitution went into effect).
Slavery wasn't outlawed in the empire until 1833.
I do not disagree with your basic premise, but don't underestimate the world-wide impact of the French Revolution on the demise of slavery.
When the Declaration of Independence was signed, slavery was legal in all of the original 13 states. By 1804, every state north of the Mason Dixon line had either abolished or passed laws for the extinction of slavery. Every nation in Europe that had been under Napoleon's control (which is every nation in Europe other than Russia, the UK and the Ottoman Empire) saw slavery and serfdom exterminated.
In the UK, Irish Catholics were emancipated in 1825 and Blacks in 1833. Even Russia emancipated its serfs in 1861. By 1861 the only places controlled by Western Powers where slavery remained were the Southern states, Britain's slave empire in India, and Brazil.