Christopher Lehmann's Washington Monthly essay, on the problem with American political fiction, makes a persuasive point. Too many political novels and movies, he argues, have as their theme the idealist who goes to Washington only to find him or herself corrupted by all those unscrupulous politicians:

In the century and a quarter since [Henry Adam's] Democracy's publication, remarkably little has changed in the depiction of American political affairs in American literature. Joan Didion offered up her own updated version of Adams's novel in 1984. The book follows a senator's wife, with the heavily symbolic name Inez Victor, who gets enmeshed in a doomed affair with a CIA operative, a reverse-image of the romantic alliance at the heart of Adams's novel. Only in Didion's vision, the seamy side of democracy has become a full-scale global delusion and imperial folly: Victor's affair takes place in Southeast Asia at the time of the fall of Saigon, and is interspersed with dyspeptic flashbacks from earlier U.S. campaign and media appearances, all reinforcing the weightless unreality of a world that is nonetheless going definitively to hell.

The arch fastidiousness of Adams and his many literary descendants seems misplaced in one crucial way: The American political system has never really staked anything on the preservation of innocence. Indeed, its structural genius is very much the reverse—using the self-interested agendas of political players to cancel each other out, interlacing the powers of government in order to limit the damage that one branch can do, and making ambition at least address, if not fulfill, the public good in spite of itself. Our federal government, as any good reader of "Federalist 10" can report, is an instrument of cynicism erected on the open acknowledgment that human nature is flawed. It has unfailingly survived (and thrived) despite the vices novelists suggest have brought it to its knees. Expecting anyone to journey to the seat of national power and deliver a Mr. Smith-like blow for the sanctity of scouting and motherhood is a bit like wanting the final act of a musical to be all gun battles and explosions: It's what the critics call a genre error.

Nothing to add, really, except four scattered things: 1) Good, now I don't feel obliged to read All the King's Men; 2) Blame the pundits! The "fall from grace" theme is a mainstay in the Washington Post op-ed page, especially the flimsy fiction that the Gingrich Republicans have somehow been "corrupted" by power since their idealist days in 1994; Or... 2b) blame Christianity! Who wouldn't expect a highly Protestant nation to be obsessed with falls from grace; 3) Hey, perhaps if we had more of the sort of political fiction, and movies, Lehmann wants to see, voters wouldn't judge purported "idealists" who come to Washington and "fail"—Clinton, inevitably Barak Obama I assume—quite so harshly... that doesn't necessarily seem like a good thing; 4) As to the original question, maybe it's hard to write good political fiction because the real-life plots are so outlandish, and the characters so twisted, that there's no sense trying to top reality—any book that included Tom Coburn, Andy Card, and Michael Brown's Arabian Horse trade would be pretty quickly dismissed as a crude absurdity.