Can someone write a thesis statement on why the constitution protected slavery?

Abraham Lincoln’s contention that the American Founding and its Constitution put slavery “in the course of ultimate extinction” runs contrary to much of the contemporary criticism of the U.S. Constitution’s stance on slavery.  Does Lincoln’s contention hold up under scrutiny?  Let us first examine the facts. Slaves were imported into and held as property all of the American colonies for more than a century. Slavery persisted despite the Revolutionary War and ratification of the Constitution, with most of the signers of the Declaration and the Constitution owning slaves, and the number of slaves steadily grew through natural increase and slave imports from abroad. Westward expansion caused sectionalism—disputes between the northern and southern sections of the new nation—to rise over slavery, and Congress continued to put off the controversy through a series of compromises name them until it could no longer be ignored.