Extreme partisanship has made it doubtful whether Congress will have the courage to forge a comprehensive, multiyear debt reduction plan. Postponing it, however, would be bad news for the country. Both parties should move toward achieving fundamental fiscal reform this year.

Here are some lessons we learned from our recent experience chairing the president’s fiscal commission, which achieved supermajority support, and the Bipartisan Policy Center’s Debt Reduction Task Force, which achieved consensus.

Bipartisan compromise is possible if all parties develop trust and mutual respect — and are willing to put their respective sacred cows on the table. Republicans and Democrats worked together on both panels to craft policies that, while no one’s first choice, aimed to solve the problem.

Failure to reach an agreement this year is not an option. We all agree that the public debt — which could surpass the size of the economy within a decade — must be reduced. Delaying action will make the choices we face increasingly difficult and sharpen the risk of a debt crisis in which bond markets force us to take painful steps.

If we fail to act, our nation could face unaffordable interest payments in excess of $1 trillion per year, which could crowd out needed investments and lead to rising interest rates and a massive debt.

A fiscally responsible plan must be bold and comprehensive — and involve shared sacrifice by all except the most vulnerable. It must restrain spending across the federal budget, slow the increase of health care costs, reform the tax code and make Social Security strong for the next 75 years and beyond with modest changes to current law.

At the same time, a plan to reduce the debt must be carefully phased in so as not to undermine the recovery.

Washington must use this opportunity to make the government work better and help growth. We must create a more cost-effective federal government and root out waste wherever we find it. Discretionary spending can be better targeted and our tax code dramatically simplified by eliminating tax earmarks and subsidies.

A credible plan must address the growth of entitlement spending caused by our aging population and unsustainable growth in health care costs. We can make Social Security financially sound for future generations through a combination of modest benefit changes and additional revenues.

Negotiators should take the best cost-control ideas from both parties, including delivery system reforms, increases in beneficiary responsibility, reductions of excess payments to providers and pharmaceutical companies, greater flexibility for states in administering Medicaid and reforms to the medical malpractice system. They should also consider reforms that bring market competition into Medicare and examine the current tax exclusion for employer-sponsored health insurance.

We can achieve substantial savings in defense spending without endangering our security — saving roughly a half-trillion dollars or more over 10 years. Savings can be achieved within our current force structure by applying Defense Secretary Robert Gates’s efficiency measures to deficit reduction, prioritizing defense investments, eliminating unnecessary or duplicative weapons systems and reforming military health care, with even greater savings possible by reevaluating our defense posture. As Adm. Michael Mullen, chairman of the Joint Chiefs of Staff, said, the U.S. debt is the “single biggest threat to our national security.”

Revenues need to be part of the solution — but as part of fundamental tax reform. Today, we spend more than $1.1 trillion a year on “tax expenditures” — credits, deductions, loopholes and exclusions, which are really just spending by another name.

Closing or tightening those loopholes can reduce the debt. At the same time, it can dramatically reduce personal and corporate tax rates, simplify the code and improve U.S. competitiveness.

Finally, to help ensure the deal is not undone by future Congresses, negotiators should include strong enforcement mechanisms with their recommendations. Statutory discretionary caps and pay-go rules are a good start. But policymakers should also consider a fail-safe mechanism, which requires action if the budget falls off track.

There is no need to reinvent the wheel. The plan put forward by House Budget Committee Chairman Paul Ryan (R-Wis.) and the framework offered by President Barack Obama have moved the debate forward by putting many proposals on the table and establishing the parameters for the discussions.

But now we need to work toward a bipartisan agreement. Administration and congressional negotiators can benefit from the bipartisan agreements achieved by the Bowles-Simpson and Domenici-Rivlin commissions and the work being done in the Senate by the Gang of Six.

The groundwork has already been laid. Time is short, our debt is mounting and credit markets around the world are watching like hawks — or vultures.