THE LABOR Department had encouraging news on Thursday: By its reckoning, the country added 288,000 new jobs last month, and the unemployment rate declined a bit.

Now will Congress stall the momentum again?

Transportation Secretary Anthony Foxx this week warned states that the federal government will have to begin withholding funding for the nation’s roads and rails starting Aug. 1. At that point, the federal Highway Trust Fund will be perilously low on cash unless Congress restocks it. States initially will lose about 28 percent of their federal transportation funding. When the federal government’s authorization to spend anything on transportation expires in September, the flow of money will dry up entirely. States, which get an average of 50 percent of their transportation funding from the federal government, already are delaying or canceling infrastructure projects — in the peak of the summer construction season.

There’s no reason for lawmakers to put the country through this uncertainty. It’s clear the money is needed. It’s clear that funding should be long-term and raised from a sustainable source of revenue, allowing for ample planning and enabling big transportation projects. And it’s clear that those who use the roads should pay for them, a policy that’s fair and efficient. All Congress needs to do is accept the obvious and approve one of the many plans that fit these criteria.

One came last month from Sen. Bob Corker (R-Tenn.) and Sen. Chris Murphy (D-Conn.). They proposed a 12-cent increase in the federal gasoline tax, to be phased in over two years; after that, the tax will be indexed to inflation. The gas tax used to raise enough to cover the nation’s transportation tab, but Congress did not index it and lawmakers haven’t increased it since 1993. Instead, they have regularly slapped together last-minute patches, scraping up revenue here and there.

Vehicles make their way north on Highway 12 during an evacuation ahead of Hurricane Arthur in Pea Island, North Carolina July 3, 2014. (Chris Keane/Reuters)

President Obama has been blasting Congress’s inaction, promising to do what he can without lawmakers. Which is not much: The president can’t replenish the Highway Trust Fund. He hasn’t been a profile in courage, refusing to endorse the needed gas tax hike. The White House at first seemed to indicate that Mr. Obama opposed the Corker-Murphy plan, but Mr. Foxx subsequently said that the administration is keeping an open mind.

The president and lawmakers in Congress should not just be open to this obvious solution to the perpetual transportation funding crisis; they should be enthusiastic about it.

At the moment, lawmakers look unlikely to pass any long-term fix before November’s midterm elections. Instead, they are working on another short-term patch funded by some sort of unrelated budget maneuver. That would be better than doing nothing. But they shouldn’t push the issue off for long with gimmicks. At some point, soon, they need to do the right thing.