As more Americans decry the lack of cooperation among leaders in Washington, D.C., that job gets more impossible by the day.

Sharp differences in policy and honest ideological disagreements are natural in our political system, and are welcomed as part of the messy give-and-take needed to govern such a sprawling, diverse republic. But when those stark positions fail to budge an inch either way toward common ground, problems go unsolved and election cycles never end.

This is the treadmill we find ourselves on, one Georgia’s senior senator has decided to step off.

Sen. Saxby Chambliss announced Jan. 25 he would not seek a third term. At 69, the Moultrie Republican is tired of fighting losing battles in the nation’s capitol as one of a scant few seeking middle-ground solutions to an economic stalemate. When he bows out in two years, his likely replacement will be steeped in the hard-line approach that no longer tolerates compromise.

So the Gang of Six — or Eight, depending on the issue and which way the wind blows — will be short one more voice. Already, several Republican senators willing to reach across the aisle were targeted for defeat in the last two elections and sent home to contemplate their sins. That leaves the number of moderate voices occupying leadership posts in Washington dwindling to a powerless few, even in the Senate, where careful deliberation and genteel demeanor used to be virtues celebrated over the House’s fiery rhetoric.

And that goes for most Democrats as well, and their party boss parked at the other end of Pennsylvania Avenue. When it came to bending even a little in the recent “fiscal cliff” debate, President Barack Obama proved to be as intractable as his foes.

It’s that mule-headed approach to politics that finally led Chambliss to decide to spend his golden years sipping single malt with friends in South Georgia rather than bang his noggin against the same walls.

Chambliss hasn’t always been a paragon of bipartisanship, but these days he stands out in comparison to his colleagues. For instance, in the last decade he was among those whose compromise created an immigration plan that would strengthen border security but provide migrant farm labor. But it was shot down by many on the hard right, and Chambliss was among those who backed down. Only after losing most of the Latino vote in the last two elections are GOP leaders now willing to reconsider such reform.

Chambliss’ recent efforts to craft a sensible approach to the nation’s budget issues were met with the same disdain. He is among a handful of lawmakers trying to craft a glass-half-full combination of revenue increases and spending cuts to stop the gusher of red ink that has hamstrung the U.S. economy. But anti-tax forces on the right have refused to budge an inch from their Grover Norquist-led pledge to never raise taxes, come hell or high water, no matter how much hotter or wetter it gets. All the while, Democrats treat every potential budget cut as if Republicans are throwing grandma into the river with a puppy tucked under each arm.

Recommendations by the Simpson-Bowles debt commission to take on a “balanced” approach were ignored by the president who created the panel. So they push the budget mess off into an uncertain future with temporary fixes while the national credit card maxes out more by the day.

“Y’all send us to Washington to make hard and tough decisions,” Chambliss said last week. “They are political in nature because everything in Washington is political. But this is our country, for gosh sakes, and here we were headed off this fiscal cliff that was a very predictable crisis and yet there was not the willingness to find that common ground, and that’s not what Saxby Chambliss is all about.”

Each election now brings in more leaders from the far left and right who can’t agree on what to order for lunch, much less pass a budget. Blame that on a voting public split along philosophical lines and unwilling to elect anyone who doesn’t follow party orthodoxy. And also on congressional districts so gerrymandered into bright red or blue enclaves that incumbents face few challengers and everyone swims in the deep end of their own ideological pools.

Chambliss’ departure won’t change that. Among the contenders lining up for his job are Republican Reps. Phil Gingrey, Paul Broun and Tom Price, none known to dip a toe in the political center. And from the Democratic side? Either an Atlanta liberal who will bump up against a low ceiling, or a more moderate sacrificial lamb who will appeal to voters of neither party and fade into oblivion.

Chambliss has his strengths and weaknesses. He alienated many before he even took office with a harsh campaign against incumbent Democrat and Vietnam veteran Max Cleland in 2002 that left a bad taste. But he has been a strong voice for national security, and has worked tirelessly to support Georgia agriculture. Both efforts will be missed.

In another era, Chambliss might be seen as an unremarkable senator of modest talents whose departure wouldn’t cause a ripple. But in a time when true statesmen are harder to find in Washington than a parking space, his exit will leave a void that likely won’t be filled.