According to the 'The American Experience' on him, US Grant was the most revered public figure in American life in the 19th century, significantly more popular than Lincoln, and yet he has regularly been evaluated as an awful President in CSPAN's survey of historians. Is this a disconnect? Why?

Not really a disconnect. As to why Grant would be highly regarded in 19th c. US, there were numerous reasons. He was, first and foremost, a war hero. After he assumed command of the Union army, it began to win more and more battles. Maybe some of this credit is not entirely deserved: the Union's advantage in force and materiél perhaps would have won under any decent leadership, and some of Grant's late campaigns, like at Cold Harbor, were very costly of men. Still: he was the one in charge when there was a victory, and was popular with his surviving men- and the opinions of Civil War veterans would be very important after the War. Grant was also un-ostentatious, plain spoken and honest; a decent man, who seemed to have worked hard for what he had become. He certainly had a heroic ending, patiently writing his memoirs as he was dying of cancer, to provide for his family.

As a President, however, Grant has gotten low marks from historians because of the corruption of his administration and because of its failure to carry out reforms. Grant may have been personally honest, but the friends and military acquaintances he brought early into his administration were sometimes not. His personal secretary, Orville Babcock, was a part of the Whiskey Ring, a group of whiskey distillers who had successfully avoided paying taxes. His first Secretary of the Interior took bribes for awarding land grants, his first Secretary of War, Belknap, took kickbacks to sell weapons to the French in the Franco-Prussian War ( the US being neutral). His brother-in-law Abel Corbin was enlisted by John Fisk and Jay Gould to get Grant to delay the Treasury Dept's periodic sale of gold, in their attempt to corner the Gold Market in 1869, the famous Black Friday of 1869. While it's true that Grant replaced them, when the scandals became known, the first years of his administration were notably corrupt.

Though Grant would begin to make steps towards some reforms- he did create the beginnings of a Civil Service- looking backwards, it's possible to see that he failed at a crucial time in US history to carry out others. Most glaring is his ending of Reconstruction and the Freedman's Bureau, slowing and stopping the Federal effort to carry out further civil rights reforms in the South. Blacks were essentially placed back under white domination for the next 90 years.

As more white settlers streamed into the western territories, he also removed Native Americans from their lands or, when necessary , let them be killed: the Modoc War in California, the Black Hills Campaign in South Dakota and the Nez Pierce Campaign in Oregon resulted in some of the most notorious massacres in US history. His commander General Philip Sheridan would say, "the only good Indians I ever saw were dead".

Again, Grant has never been accused of being corrupt himself. His military experience in a way made him unfit for the role: a military commander expects the highest loyalty from his officers and men, and is expected to be loyal to them in return. Grant did not understand that in politics the temptations of power could often overwhelm those loyalties- that his secretary Babcock could be bribed simply for being close to Grant. He was, in the end, someone who had never expected a high political office, never trained to be a chief executive, and never quite measured up to the task.