In the House, Speaker John Boehner has refused to rule out the possibility of threatening either a narrow or a full-scale shutdown to get Mr. Obama to back off his plans. Did Mr. Boehner learn nothing from the 16-day shutdown the House imposed on the country in October 2013? That deeply irresponsible act — a futile tantrum aimed at the health reform law — harmed hundreds of thousands of government employees, along with countless citizens who depend on important programs. It hurt the reputation of the country, and particularly that of the House and the Republican Party.

Still, he has decided not to anger the most extreme wing of his party, which is agitating for obstruction. When one prominent House Republican — Harold Rogers, chairman of the Appropriations Committee — pointed out that these tactics probably wouldn’t work because many immigration services are funded by fees, not appropriations, he was shouted down by House leaders, who said that he was not speaking for them.

Mr. Obama would presumably veto any spending bill that damages the immigration system or domestic security, at which point Republicans would no doubt blame any resulting shutdown on him. As Senator Ted Cruz of Texas wrote recently in Politico, “If the President is unwilling to accept funding for, say, the Department of Homeland Security without his being able to unilaterally defy the law, he alone will be responsible for the consequences.”

When Congress returns on Monday, it will have only a few business days to choose its approach before the current spending bill runs out on Dec. 11. To be the “mature governing body” that some Republicans promised, Congress needs to pass a full year’s spending bill for every department, along the lines of the bipartisan budget agreement approved last December.

Once Republicans take over both houses of Congress next year, they have every right to pass an immigration bill of their choosing, which Mr. Obama would have a right to veto. But threatening to shut down the government or any part of it to achieve their aims is outrageous.