"Any president who tried to attack his own assassin is worth writing about," Meacham says.

But Meacham quickly turns serious when tallying the seventh president's historical importance -- and personal flaws.

"He is the president [of his era] most like us," the Newsweek editor says in a phone interview from Charleston, South Carolina."He was capable of great grace, but he could also be terribly cruel. ... In his complexities, I saw our own."

It's those kinds of contradictions that have kept historians revisiting Jackson for the past 175 years, and got Meacham going on"American Lion" (Random House). Jackson was the first president not from Virginia or Massachusetts, a frontiersman and general not connected to the Founding Fathers or Washington aristocracy. He was viewed with distaste by some, admiration by others.

Some Washington colleagues, including Kentucky congressman Henry Clay, believed he was little more than an erratically tempered hick with dictatorial impulses.

"I cannot believe that the killing of 2,000 Englishmen at New Orleans qualifies a person for the various difficult and complicated duties of the Presidency," Clay once said, referring to Jackson's victory at the 1815 Battle of New Orleans.

But he also was the subject of hero worship among citizens who admired him for his military leadership, his steadfast loyalty to national ideals, and the fact that he wasn't what would now be called a"Washington insider."

Meacham, who had access to a trove of heretofore-unreleased letters from Jackson intimates, sees him as closer to the latter....