“Catastrophic.” “Calamitous.” “Major crisis.” “Self-inflicted wound.” Those are some of the ways Ben Bernanke, the chairman of the Federal Reserve, has described the fallout if Congress fails to raise the debt limit by the Aug. 2 deadline.

In Congressional testimony this week, Mr. Bernanke also warned that the Fed would not be able to fully counter the damage from a default, including the possibility that spiking interest rates would roil borrowers worldwide and worsen the federal budget deficit by making it costlier to finance the nation’s debt.

That’s not all of it. Brinkmanship over the debt limit is only one of many epic economic policy blunders now in the making. Even if lawmakers raise the debt limit on time, the economy is weak and getting weaker, as evidenced by slowing growth and rising unemployment.

Instead of coming up with policies to strengthen the economy, the Republicans are demanding deep, immediate spending cuts, which would only add to current weakness. The White House, meanwhile, has suggested cuts should be phased in slowly and has said that more near-term help would be good for the economy. That is a better approach. But President Obama has done too little to argue the case, on Capitol Hill or with the public.