Rancor and recrimination are suffocating Washington like a summer heat wave, but the nasty tone of the debate obscures an important point of agreement. Leaders in both parties now agree that Congress is a failure. It cannot, they concede, make the painful decisions necessary to defuse the country’s exploding budget deficits.

In exchange for a vote to increase the government’s borrowing authority, Republicans have demanded massive cuts in federal spending. House Speaker John Boehner and President Obama tried, and failed, to negotiate a “grand bargain” that would reduce benefits and raise revenues. Boehner and the Senate’s Democratic leader, Harry Reid, then advanced competing, and more modest, deficit reduction plans that would do little to solve the long-term problem.

But look closely. Both Boehner and Reid have proposed some form of congressional commission empowered to make the wrenching decisions that the country needs but that lawmakers cannot, or will not, make on their own. Both leaders agree that their colleagues should be forced to vote, up or down, on the commission’s recommendations, without filibusters or other dilatory tactics.

This is a sad day. The U.S. Congress is the greatest legislative body ever devised. But it has lost the capacity to act, even in the face of a profound threat to the national interest.

As Obama noted, “America … has always been a grand experiment in compromise.” Today, “compromise has become a dirty word,” as the president put it. Anyone who tries to be conciliatory is denounced as a traitor by hardliners who sound more like Sunnis and Shiites than Democrats and Republicans.

Without compromise, Congress collapses. A commission is a lousy idea, but it’s a lot better than nothing, and nothing is what Congress seems prepared to produce on its own.

Of course, this is hardly a new concept, and many commissions don’t work. The Bowles-Simpson panel, for example, appointed by President Obama last year, produced a far-reaching proposal with almost $4 trillion in deficit-reduction measures. But it evoked a tepid response in many quarters and never came to a vote.

The Defense Base Closure and Realignment Commission, or BRAC did work. It grew out of the same understanding that Boehner and Reid now reflect: Some decisions are too politically risky for Congress to handle.

In the late ‘80s, the issue was closing wasteful military bases that often provided economic lifelines to local communities. As its official website puts it, “The BRAC Commission was created to provide an objective, thorough, accurate and non-partisan review” of the military’s real needs. Congress could not alter the list of proposed closures, it could only vote yes or no, and five reviews over 16 years shuttered more than 350 redundant installations.

Cutting the budget is a far more complex and contentious problem than closing military bases, and Congress is a very different place today than it was when BRAC was invented. A study of voting patterns by the National Journal shows that in dramatic fashion.

In 1982, the Journal identified a centrist bloc that fell between the most liberal Republican and most conservative Democrat. Fully 60 senators fit that description — 36 Democrats and 24 Republicans.

The number has dropped steadily since then, and last year the most conservative Democrat, Ben Nelson of Nebraska, had a more liberal voting record than the most left-leaning Republicans, Susan Collins and Olympia Snowe of Maine and George Voinovich of Ohio. By this measurement not a single senator could be considered a centrist.

“Neither side has a middle, and I think that’s the main problem,” Prof. Charles Stewart of MIT told The Washington Post. Without a middle, deal-making and consensus building is almost impossible.

Moderate Southern Democrats and progressive Northern Republicans have virtually disappeared from Capitol Hill. Those who remain in Congress have been pushed out of the center by extreme partisans demanding ideological orthodoxy.

We don’t like commissions. We’d much prefer Congress to do its work through the normal legislative process. But as Boehner and Reid now admit, at a time when compromise is a “dirty word,” lawmakers might have to be saved from themselves.