WE Americans live in a society awash in historical celebrations. The last few years have witnessed commemorations of the bicentennial of the Louisiana Purchase (2003) and the 60th anniversary of the end of World War II (2005). Looming on the horizon are the bicentennial of Abraham Lincoln’s birth (2009) and the sesquicentennial of the outbreak of the Civil War (2011). But one significant milestone has gone strangely unnoticed: the 200th anniversary of Jan. 1, 1808, when the importation of slaves into the United States was prohibited.

This neglect stands in striking contrast to the many scholarly and public events in Britain that marked the 2007 bicentennial of that country’s banning of the slave trade. There were historical conferences, museum exhibits, even a high-budget film, “Amazing Grace,” about William Wilberforce, the leader of the parliamentary crusade that resulted in abolition.

What explains this divergence? Throughout the 1780s, the horrors of the Middle Passage were widely publicized on both sides of the Atlantic and by 1792 the British Parliament stood on the verge of banning the trade. But when war broke out with revolutionary France, the idea was shelved. Final prohibition came in 1807 and it proved a major step toward the abolition of slavery in the empire.

The British campaign against the African slave trade not only launched the modern concern for human rights as an international principle, but today offers a usable past for a society increasingly aware of its multiracial character. It remains a historic chapter of which Britons of all origins can be proud.