For all the poll swings, breathless analysis, and sheer uncertainty in the lead-up to Nov. 2, there is one thing you can say for certain about these elections: they did nothing to end congressional polarization. The two parties seem farther apart than they have been for decades — and appear less inclined to bridge that gap than I’ve ever seen.

The reasons for this are so numerous that I wonder if we can ever find our way out. Yet we can’t begin to address the problem unless we understand it — and it is a problem, if you believe that our system of government should allow us to discuss rationally the issues that confront us without partisan bickering at every step.

The troubles are most obvious on Capitol Hill, where the political center struggles to survive. The leaders of both parties have made a cold calculation that they can accomplish more by not cooperating with each other than by striving to find common ground. The Republicans have rebuilt their political standing through unyielding opposition; the Democrats have notched their legislative goals by finding ways to short-circuit Republican involvement.

The power that has flowed to congressional leaders on both sides of the aisle over the past two decades has made it possible for them to polarize Congress in pursuit of electoral advantage. We have today a system that rewards politicians for conflict and confrontation, and encourages them to demonize opponents.

In recent years, many members of Congress have either come from the extremes of their party, or know that in order to win a primary or prevent a strong opponent in the primary, they have to appeal to the activist — and hence more immoderate — members of their party. They increasingly depend on an activist base for votes, money, and job security.

District lines drawn to boost the chances of one or another party don’t help, either; they make it more likely that the real election will be in the primary, not the general election. The torrents of money that now flow into election contests help to exacerbate and intensify differences. These trends have seriously eroded the political center in Congress.

Meanwhile, the tone on Capitol Hill has grown more shrill. Where comity was generally the order of the day, now the two parties segregate themselves, driven by scheduling and preference. The plain truth is that Republicans and Democrats don’t spend much time with one another, don’t know one another nearly as well as they should, and so find it easier to take their cues from shoutfests and the blogosphere and demonize one another.

“Politics has become more moralistic from both left and right,” Robert Samuelson wrote recently in The Washington Post. “Idealistic ideologues campaign to ‘save the planet,’ ‘protect the unborn,’ ‘reclaim the Constitution.’ When goals become moral imperatives, there’s no room for compromise. Opponents are not just mistaken; they’re immoral. They’re cast as evil, ignorant, dangerous, or all three.”

What makes this perplexing — but also suggests some reason for hope — is that this extreme division is mostly at the level of political elites, not among the broad mass of Americans. As political scientists Morris Fiorina and Samuel Abrams wrote of ordinary Americans in 2008, “There is little indication of increasing polarization, namely, the middle losing people to both extremes. Rather, we see a largely centrist public drifting slightly rightward on some issues, slightly leftward on others, but with only very small declines … in the number of moderates.” Of course, that very dynamic has led to rough parity between the two parties, which makes every election crucial and every vote in Congress highly politicized as they scrap for whatever advantage they can gain.

All of this is exacerbated by our now-constant media cycle, which pushes for immediate answers to a steady barrage of questions. Forced to take a position, politicians harden into them, lest they be accused of flip-flopping and defined in an unflattering light. Overall, the media has become more impulsive and less thoughtful, thriving on combat and shocking statements, not analysis.

One arena in which Americans do seem unambiguously divided is where they find their news. As far back as 2004, the Pew Center for People and the Press noted, “Political polarization is increasingly reflected in the public’s news viewing habits.” The situation has only grown worse over the last six years, which means that people are often making decisions based on entirely different “facts” presented to them by different news outlets that merely confirm their biases. Small wonder that it is getting more difficult for the politicians who represent them to find common ground.

Lee Hamilton is director of the Center on Congress at Indiana University. He was a member of the U.S. House of Representatives for 34 years.