Four years ago, Barack Obama won the White House by convincing his supporters that he was not just another candidate, but a figure above and beyond politics.

In 2012, after a term marked by partisan warfare and economic malaise, that vision now looks excessively naive. Obama’s supporters, especially the young, have lost their innocence about the power of idealism in politics, and about the possibility that a leader can stay above the fray.

Many of them now wish that Obama was not above politics, but right in the thick of it -- using fair means or foul to get his agenda through Congress, attacking his opponents instead of retreating into his cerebral detachment. In short, they wish that Obama had a little more in him of Willie Stark, the ruthlessly effective politician at the center of the greatest novel ever written about American politics: “All the King’s Men,” by Robert Penn Warren.

Stark, the charismatic and sinister governor known to one and all as “the Boss,” is based on Huey Long, who during the Depression became the virtual dictator of Louisiana and a potent national presence. Like his model, Stark is a demagogue, able to whip up a frightening fervor in his audience: “There is nothing like the roar of a crowd when it swells up, all of a sudden at the same time, out of the thing which is in every man in the crowd but is not himself.”

No Constraints

Yet as Warren shows, Stark’s contempt for legalities and his willingness to extort, blackmail and threaten is what makes him such an effective leader. Unlike Obama, he is always able to get his plans through the legislature. In some sense he is even a liberal: He takes pride in taxing the rich and building roads, schools and hospitals for the poor, whom more decorous politicians have ignored. He represents the temptation of power unconstrained by law -- which can be a power for good as well as evil.

If Stark ends up as the most cynical kind of “realist” -- “It’s dirt makes the grass grow. A diamond ain’t a thing in the world but a piece of dirt that got awful hot,” he says to Jack Burden, the book’s narrator -- it’s only because he started out as the most innocent idealist, a true believer in hope and change.

When Burden, a journalist, first meets Stark, he is merely Cousin Willie, a country boy who drinks orange pop instead of liquor and is absolutely ruled by his pious Baptist wife. Willie’s political career begins when he refuses to go along with a boondoggle involving the building of a schoolhouse. The local fame he earns from this episode brings him to the attention of the state’s party bosses, who enlist him in a political scheme: They persuade Willie to run for governor, knowing full well that he hasn’t got a chance to win, in order to split the rural vote and elect their preferred candidate.

Willie Stark goes along with this plan because, Burden ruefully tells us, he is a romantic about America, and sincerely believes he can win election purely on the strength of his idealistic rhetoric. A self-educated man, everything he knows about the country comes from books, and the books are full of simple, heroic figures like himself.

It is the shock of discovering that politics is not virtuous, that the campaign he believed to be a crusade was actually a charade that turns him into a vicious, no-holds-barred political infighter.

Fallen Idols

Long afterward, Stark remembers his naivete with self-contempt: “He wanted to know the history of the country. He had a college text book, a big thick one. Years later, showing it to me, he prodded it with his finger, and said: ‘I durn near memorized every durn word in it. I could name you every name. I could name you every date.’ Then he prodded it again, this time contemptuously, and said: ‘And the fellow that wrote it didn’t know a God-damned thing. About how things were. He didn’t know a thing. I bet things were just like they are now. A lot of folks wrassling round.’”

For Warren, a Southern writer dealing with a Southern story, the bitterest pill is the revelation that even Southern chivalry turns out to be a myth. Jack Burden, born in a town named for his family, comes from a wealthy, civilized, aristocratic class which is all that remains of the antebellum grandeur. The giants of his childhood are men like Judge Irwin, a father figure to him, and Governor Stanton, the father of his friend Adam and his first love Anne. All these people look down on Stark with total contempt, seeing him as a redneck bully who vandalizes every principle of law and decorum.

Yet the plot turns on Burden’s discovery that those Southern aristocrats were themselves little better than corrupt politicians. Adam Stanton, Jack says bitterly, “has lived all his life in the idea that there was a time a long time back when everything was run by high-minded, handsome men wearing knee breeches and silver buckles or continental blue or frock coats ... who sat around a table and candidly debated the good of the public thing.”

But even Thomas Jefferson, we know now, had plenty of secrets to hide; he too was one of the folks “wrassling around.” And the novel leads up to the revelation that even the sainted Judge Irwin once accepted a bribe from a power company in exchange for a favorable ruling. The falling of the old idols leaves men such as Jack Burden morally adrift, uncertain if there is anything or anyone left to believe in. As his name suggests, he bears the burden that today’s disillusioned young Obama voters also carry, the realization that there is no room for purity in politics.

“All the King’s Men” takes a bitter pleasure in shattering the reader’s faith that good work is done by good men. Stark’s brand of politics, while dictatorial and corrupt, at least manages to get things accomplished; you may not feel good about voting for him, as so many people felt good about voting for Obama in 2008, but there is no danger that he will get stuck in partisan gridlock.

There is a seductive force behind his insistence that his evil is simply the means of doing good. All around the state, Warren writes, you can find bigger-than-life-sized posters of Willie Stark bearing the slogan, “My study is the heart of the people.” They are signs of a cult of personality, but they also capture a frightening possibility: that in changing himself from an idealist to a ruthless demagogue, Stark is simply giving the American people what they really want.

(Adam Kirsch is a senior editor at the New Republic and a columnist for Tablet magazine. He is the author of “Why Trilling Matters.” The opinions expressed are his own. Read Part 1, Part 3, Part 4 and Part 5 of his series on classic political novels.)

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To contact the writer of this article: Adam Kirsch at adam.kirsch@hotmail.com.

To contact the editor responsible for this article: Katy Roberts at kroberts29@bloomberg.net.