President Biden’s assertion that he’s ready to sign a border deal — one that would make it much harder for migrants to enter the United States — is a necessary and long overdue step to restore the public’s confidence in the federal government’s ability to maintain control over immigration.

The crush of asylum seekers crossing the southern border has overwhelmed the government’s capacity to deal justly with their claims. The needs of the migrants have strained the resources of cities and towns across the country; in the absence of federal help, these communities are finding it difficult to maintain humane conditions for everyone who crosses. This situation is untenable.

Democrats have been too slow to respond to the increasingly urgent pleas from mayors, governors and voters to act. Republicans deserve credit for pressing for action, and they ought to be celebrating that Mr. Biden has now accepted many of the strict border security measures that they have long pushed for. But Donald Trump, the front-runner for the Republican presidential nomination, insists that Republicans reject the legislation taking shape in the Senate. Several Senate Republicans have said Mr. Trump is blocking it to keep immigration alive as a campaign issue. Senator Todd Young of Indiana called this move to derail the negotiations “tragic.” Mr. Young and the other Senate Republicans nevertheless continue to work with their Democratic colleagues to hammer out a compromise.

House Republicans, however, don’t seem interested in writing laws; they have instead submitted to Mr. Trump’s demands. The House speaker, Mike Johnson, says any bill the Senate sends to the House will be “dead on arrival.” Instead of negotiating with Democrats, they are pressing ahead with a farcical effort to impeach Alejandro Mayorkas, the secretary of homeland security.

Republican leaders outside of Congress are engaged in other forms of sabotage. The Oklahoma Republican Party voted to censure the Republican senator James Lankford for his role in leading the Senate negotiations. The Republican governor of Texas, Greg Abbott, who has long used human lives as political props, has directed the Texas National Guard to impede the work of federal immigration officers along the southern border. These actions have set off a constitutional standoff between the state and federal governments and created dangerous conditions, including regular reports of people drowning or being injured by the barbed wire the state installed over the objections of federal authorities.

These political maneuvers are counterproductive and a distraction from the scale of this issue: The number of migrants entering the United States from the southern border has never been greater. As Miriam Jordan of The Times reported, 2.5 million people crossed in the 2023 fiscal year, “more than live in most U.S. cities.”