Answer:
Abraham Lincoln is often considered the greatest president for his leadership during the American Civil War and his eloquence in speeches such as the Gettysburg Address.
Step-by-step explanation:
Many historians rate America's 15th chief executive, James Buchanan, as the most inept occupant of the White House due mainly to the fact that he took no action to unite a country sharply divided over the issue of slavery and did nothing to stop Southern states from seceding in the lead-up to the Civil War.