LIKE SO many procrastinating students putting off their summer homework assignments, Congress has postponed much of the United States' essential business until after the August recess — and left itself only 12 days on the legislative calendar to get it all done now that lawmakers are back in Washington. This legislative backlog could and should have been avoided if Capitol Hill worked under regular order, leavened by a modicum of bipartisanship. Instead, what we have had is attempted rule by a Republican majority that has been too fractious to get even basic things done. By terrible accident, that means those Republicans will now have to act amid a political atmosphere transformed by Hurricane Harvey, and the need for billions of dollars in federal aid to repair the damage.

The to-do list includes a new spending bill, which has to pass by Sept. 30, when the current fiscal year concludes, lest the federal government be forced into another partial shutdown. In that respect, Harvey may have the unintended fortunate effect of defusing any attempt by House Republican ultras to threaten a shutdown over funding President Trump's border wall, which doesn't seem like such a priority anymore. The National Defense Authorization Act, which sets forth policy and priorities for the vast military establishment, is also due for renewal. Each of the above can be extended via short-term legislation. The same is not true for the federal debt limit, which must be extended before mid-October, unless Congress wants to find out what happens when the Treasury cannot meet all its obligations on time. That could destabilize the "risk-free" nature of U.S. government debt, upon which financial markets worldwide and, by extension, the global economy depend.

Treasury Secretary Steven Mnuchin has urged lawmakers to extend the debt limit by no later than Sept. 29, which seems prudent given the economic uncertainty bred by Harvey and the fact that the Treasury is supposed to make a giant $81 billion payment to the military retirement trust fund by Oct. 2. Pre-Harvey, Mr. Mnuchin also repeatedly called for the extension to be "clean" — or unconditional. But over the weekend he suggested that it be included in a hurricane relief bill. That could be a risky maneuver, given the inevitable resistance from the GOP right; it's also somewhat illogical, since the government would not be borrowing to enable new spending, but to pay for that which Congress has already approved.

Republican hard-liners in the House think it's wrong to pass a higher debt limit unless it's connected to spending cuts. From time to time this year, Mr. Trump's budget director, Mick Mulvaney, a former member of the House Freedom Caucus, has dropped hints that he agrees with his old colleagues, which has not helped matters. Nevertheless, the entire top tier of Republican leadership — Mr. Trump, House Speaker Paul D. Ryan (Wis.) and Senate Majority Leader Mitch McConnell (Ky.) — have repeatedly insisted that they intend to raise the debt limit. They should make a "clean" bill Job One. Even amid all the other pressing legislative deadlines, preserving the United States' basic financial credibility must take precedence.