In December, a panel of outside advisers tapped by President Obama could not have been more clear: The authority of the National Security Agency expanded at the expense of individual privacy the past dozen years. On Tuesday, the president publicly embraced one of the panel’s leading recommendations. He wants to overhaul the sweeping collection of telephone records by the intelligence agency.

The concern has not been that the agency abused its authority. There is no evidence of such excess. Rather, the real potential exists, requiring improved oversight and safeguards to protect against bad actors.

As things stand, the agency systematically collects logs of all American phone calls. A special court oversees the program, yet a select group of agency analysts has the power to authorize the search of individual telephone records (numbers, time, duration — not content). The president has proposed halting this practice. The agency no longer would collect the records. They would stay with the phone companies. The agency would be required to obtain a court order to gain access to the records of callers linked to a suspect. It would be permitted to make just two “hops” from a suspect, narrowing significantly the number of callers tracked in a sweep.

In the main, these steps represent a helpful adjustment. The expanded authority of the National Security Agency stems from the Sept. 11 attacks, the do-whatever-it-takes thinking of the George W. Bush administration. The worry has been that the agency loses an element of speed if required to meet a higher level of permission from the courts. What the panel of expert advisers found is that the data mining has not been necessary for stopping terrorist attacks.

So slowing the process won’t hurt. The program does complement other efforts to fight terrorism. Thus, preserve the work without putting at risk the privacy and dignity of Americans.

There is much room for argument about the details of an overhaul of such surveillance, as the current congressional debate shows. Why require phone companies to hold the data for government purposes? Better to create a separate storage operation. The oversight process would benefit from a public interest advocate available to the courts, pressing for civil liberties.

What President Obama got right in his statements this week is the overarching need “to win back the trust … of ordinary citizens.” Terrorists gain an advantage when they succeed in stirring fear that leads to the erosion of cherished principles. That is what happened with the expansion of the National Security Agency. Now the president has called for the required repair.