issue of slavery and emancipation, as the Congressional debate over slavery and its extension caused a dangerous north–south rift among the states, with talk of a northern confederacy in New England. The violent attacks on white slave owners during the Haitian Revolution due to injustices under slavery supported Jefferson's fears of a race war, increasing his reservations about promoting emancipation at that time. After numerous attempts and failures to bring about emancipation, Jefferson wrote privately in an 1805 letter to William A. Burwell, "I have long since given up the expectation of any early provision for the extinguishment of slavery among us." That same year he also related this idea to George Logan, writing, "I have most carefully avoided every public act or manifestation on that subject." Historical assessment Scholars remain divided on whether Jefferson truly condemned slavery and how he changed. Francis D. Cogliano traces the development of competing emancipationist then revisionist and finally contextualist interpretations from the 1960s to the present. The emancipationist view, held by the various scholars at the Thomas Jefferson Foundation, Douglas L. Wilson, John Ferling, and others, maintains Jefferson was an opponent of slavery all his life, noting that he did what he could within the limited range of options available to him to undermine it, his many attempts at abolition legislation, the manner in which he provided for slaves, and his advocacy of their more humane treatment. One month before the Act Prohibiting Importation of Slaves came into effect, in his annual message to Congress, Jefferson denounced the "violations of human rights." He said: The revisionist view, advanced by Paul Finkelman and others, criticizes him for holding slaves, and for acting contrary to his words. Jefferson never freed most of his slaves, and he remained silent on the issue while he was president. Contextualists such as Joseph J. Ellis emphasize a change in Jefferson's thinking from his emancipationist views before 1783, noting Jefferson's shift toward public passivity and procrastination on policy issues related to slavery. Jefferson seemed to yield to public opinion by 1794 as he laid the groundwork for his first presidential campaign against Adams in 1796. Historian Henry Wiencek said Jefferson "rationalized an abomination to the point where an absolute moral reversal was reached and he made slavery fit into America's national enterprise." Jefferson–Hemings controversy Claims that Jefferson fathered Sally Hemings's children have been debated since 1802. That year James T.