SETTING THE TERMS for an intervention in Libya, President Obama said on March 18 that “all attacks against civilians must stop.” Moammar Gaddafi, he said, “must stop his troops from advancing on Benghazi, pull them back from Ajdabiya, Misurata and Zawiya, and establish water, electricity, and gas supplies in all areas. Humanitarian assistance must be allowed to reach the people of Libya.”

Nearly six weeks later, NATO airstrikes have driven the Gaddafi forces away from Benghazi and Ajdabiya. But Zawiya is occupied by government units, and Misurata — the country’s third-largest city — is besieged. This week shells and rockets have been raining down on the port, where thousands of refugees have gathered in the hope of being evacuated. The toll of the dead and wounded rises every day.

On Wednesday the Associated Press quoted the European Union’s commissioner for humanitarian aid as saying the attacks have interrupted the delivery of supplies and “it is close to impossible for our humanitarian partners to evacuate the wounded and civilians by sea.” Drinking water is running short.

It would seem pretty clear that the United States and its allies are failing in the basic mission of civilian protection that Mr. Obama laid out. But this failure — and the human suffering it is causing — has not seemed to elevate the administration’s sense of urgency. “We will continue to pursue the policy the president has set forth,” a senior State Department official told reporters Tuesday. “We’ve been at this now for just over a month . . . and there has to be some degree of patience in terms of executing the terms of this mission.”

An appeal for patience would be logical if the United States and NATO were doing everything possible to stop the killing of civilians under the terms of U.N. Resolution 1973. But they are not. Mr. Obama continues to withhold U.S. A-10 and AC-130 warplanes from the operation, even though they are considerably more effective at attacking ground targets than are the aircraft of NATO allies. Though Mr. Obama has said that the U.N. resolution would allow the supply of arms to rebels fighting the regime, he has not authorized deliveries — and he did not approve a $25 million shipment of non-lethal supplies until Tuesday, 11 days after the State Department first notified Congress of the aid.

U.S. Ambassador to Libya Gene Cretz said Wednesday that the State Department’s envoy to the rebel interim government had deemed it “worthy of our support.” But unlike Britain, France and Italy, the administration has yet to recognize the Transitional National Council as Libya’s legitimate government.

The allies are stepping up their campaign — but in tiny increments. Last week the Pentagon responded to appeals from Britain and France by authorizing two drones already deployed in Libya to carry out strikes as well as surveillance. On Monday Mr. Obama spoke by telephone with Italian Prime Minister Silvio Berlusconi, who agreed to allow Italian planes to join the attacks.

If sustained long enough, the current operation might be enough to turn the tide against the regime. But time means lives. Libyans are dying in large numbers: The U.S. ambassador suggested that between 10,000 and 30,000 already may have been killed. If more steps can be taken to save Libyans — the redeployment of U.S. planes, weapons for the opposition, ground spotters to call in airstrikes — Mr. Obama should authorize them.