The air is thick with lies, deceptions, distortions, demagoguery, sleaze, and vicious rhetoric, uttered every day by President Bush, John Kerry, or their surrogates. Both candidates offer evasion and snake-oil non-remedies for dire national problems, ranging from the existential threat of nuclear terrorism, to the war in Iraq, to global warming, to the looming Social-Security-Medicare-deficit disaster. And each campaign is whipping its most partisan supporters into a frenzy of hatred for the opposing party.

One candidate is an intellectually shallow, closed-minded, strangely smirking, free-spending, hard-right culture warrior who combines smug ideological certitude with stunning indifference to facts and evidence, who is obsessed with shifting the tax burden from the wealthiest Americans to future generations, who claims virtually unlimited power to suspend constitutional liberties, who has alienated millions of America’s onetime admirers abroad, and who has never made a mistake he would not repeat. The other is a both-sides-of-tough-issues, unlikable, aloof, cheap-shotting, free-spending political careerist whose domestic policies might make the Bush deficits even worse, whose Iraq policy shifts with every political wind, and who has long been close to his party’s quasi-pacifist, lawsuit-loving Left. Both seem less qualified for the job than do many others who will never be president: Colin Powell, Sam Nunn, John McCain, Joseph Biden, Richard Lugar, Joe Lieberman, Bob Graham, Dick Gephardt, Arnold Schwarzenegger, and Jennifer Granholm, for starters.

It’s almost an act of faith to cling to Winston Churchill’s wisdom that democracy is the worst form of government-except for all the other ones. With the stakes so high, why has the quality of our politics sunk so low? Are there institutional reforms that might make it better? I will grope for answers in this and a future column.

American politics never has been and never will be a thing of beauty, unless and until genetic engineers purge selfishness, dishonesty, tribalism, and irrationality from human nature. But it didn’t used to be this ugly. And it doesn’t have to be. The most important source of the current ugliness is the eclipse of moderate centrists, who reflect the views of most voters, by ideologically impassioned conservatives and liberals, who dominate our major parties and interest groups.

One consequence of our polarized political discourse is the inability of conservatives and liberals in Congress and elsewhere to collaborate on pragmatic, compromise solutions to pressing national problems. It’s not easy to collaborate when you see those who don’t share your views as corrupt, stupid, or fanatical. Gone are the days when House Speaker Tip O’Neill and Republican Leader Bob Michel saw one another as friends, both on the golf course and in the Capitol.

Less obvious, but equally pernicious, is the tendency of polarized politicians to focus on divisive, emotionally charged issues, such as abortion and gun control, that obsess powerful interest groups but are less important to most voters. Polarization also ratchets up the level of anger, mendacity, and misleading rhetoric, as politicians appeal to the emotions of their political bases by distorting the views and smearing the characters of their opponents.

Such campaigns convince many moderates that politics is a nasty business and a waste of time. The honest grappling with hard issues that characterized the Federalist Papers and the Lincoln-Douglas debates has almost disappeared.

Are polarized politics the inevitable outgrowth of an American public "more bitterly divided than it has been for a generation," in the words of The Economist? Must we watch as "the red states get redder, the blue states get bluer, and the political map of the United States takes on the coloration of the Civil War," to borrow from the columnist E.J. Dionne? Not exactly. Florida, to pick one "red state," would have been in the "blue" category four years ago had another 269 of its 6 million voters chosen Vice President Gore over Bush. And three of the bluest states-New York, Massachusetts, and Rhode Island-have Republican governors.

Nor are most "red" and "blue" voters becoming more bitterly polarized. "The great mass of the American people … are, for the most part, moderate in their views and tolerant in their manner," political scientist Morris Fiorina writes (with two collaborators) in a compelling 2004 book, Culture War: The Myth of a Polarized America, which is backed by impressive data. "There is little evidence that Americans’ ideological or policy positions are more polarized today than they were two to three decades ago, although their choices often seem to be. The explanation is that the political figures Americans evaluate are more polarized. A polarized political class makes the citizenry appear polarized, but it is only that-an appearance."

If this year’s Republican and Democratic nominees were John McCain and Joe Lieberman, for example, we would have a far more serious, more honest, more healthy campaign, and would elect a better man for the job than Bush or Kerry.

The polarization of our politicians, activists, journalists, and intellectuals is rooted, to some extent, in traits and trends unlikely to be reversed, such as the decline of the political parties, the rise of single-issue groups, the urge to stick reflexively with one’s political "team" rather than think hard about issues, and the apparent increase in voters’ ideological rancor as they become more educated. But polarization also has some systemic causes, which may be amenable to reform.

The worst systemic cancer on our body politic is the ever-more-egregious gerrymandering of House and state legislative election districts-especially the bipartisan, incumbent-protection variety. A leading example is the agreement of California Democrats and Republicans in 2001 to draw 33 safe Democratic congressional districts, 20 safe Republican districts, and not one competitive district. Such gerrymandering has become so prevalent nationwide that the general election winners in all but about 35 of the nation’s 435 congressional districts this year have already been predetermined by the officials who drew the lines.

Worse, the "people’s House" has become grossly unrepresentative of the people. The reason is that members need fear challenges only in primaries dominated by the fiercest conservative and liberal partisans. So moderate centrists have almost disappeared from the House, replaced by the most conservative of Republicans and the most liberal of Democrats.

Gerrymandering also has an indirect, less dramatic polarizing effect on the Senate and the presidency. Candidates for these offices run statewide (and nationwide) and must therefore appeal to a broader constituency. But many senators climb the political ladder by winning in gerrymandered House and state legislative districts. They bring with them the same political philosophies, advisers, and contributors that they had before.

Statewide candidates must also win primaries in which only about 8 percent (in Republican contests) or 10 percent (in Democratic contests) of voting-age citizens participate, according to Curtis Gans, director of the Committee for the Study of the American Electorate. Whether this in itself has a large polarizing effect on Senate and presidential races is debatable. Gans thinks not, stressing that campaign contributors and primary voters look for people who can win the general election. That certainly helps explain how John Kerry overtook Howard Dean.

But those who vote in primaries-and who work in campaigns, and donate money, and otherwise focus on politics-are the most intense, ideologically committed conservatives and liberals, and they prefer nominees with similar views. "The problem," explains Fiorina, "is that people who care deeply also tend to have extreme views."

These are among the reasons why even statewide primaries often choose nominees-like Bush and Kerry-who are further to the right and left of center, respectively, than are most other members of their parties, not to mention the growing numbers of independents. And why more-centrist figures such as McCain and Lieberman cannot win presidential nominations.

It does not have to be this way. Gerrymandering has become far more extreme in recent decades, a trend that could and should be reversed. And possible reforms of both the primary and general election systems have the potential to increase participation by centrist voters and elect moderate candidates.

Unfortunately, elected officials have a vested interest in perpetuating the systemic causes of polarization. And the institutions that should be pointing the way toward solutions-the Supreme Court and the Fourth Estate-have instead aggravated the problems. They should do better.

To be continued.