WASHINGTON — Defense Secretary Ashton B. Carter said Sunday that Iraqi forces had demonstrated “no will to fight” against the Islamic State, blaming them for a retreat that led to the terrorist group’s victory in capturing the city of Ramadi.
While that assessment of Iraqi security forces has been voiced in Congress and by analysts, Carter’s remarks on CNN’s “State of the Union” were some of the strongest yet from the administration about Iraq’s repeated inability to hold and take back territory from the Islamic State.
“They were not outnumbered. In fact, they vastly outnumbered the opposing force and yet they failed to fight and withdrew from the site,” he said. “That says to me and, I think, to most of us, that we have an issue with the will of the Iraqis to fight.”
Carter said US and allied airstrikes have been effective, and he reiterated the Obama administration’s opposition to sending American ground troops to work alongside Iraqis on the front lines to offer more accurate guidance for bombing.
The White House declined to comment on Carter’s remarks.
Some members of Congress, including Senator John Mc-Cain, Republican of Arizona, have called on President Obama to authorize troops to accompany Iraqi forces on the battlefield to call in specific locations for bombing.
The administration is focused on continuing to bolster the Iraqi forces, Carter said.
“If there comes a time when we have to change the kinds of support we give, we will make that recommendation,” Carter said. “But what happened in Ramadi was a failure of the Iraqi forces to fight, and so our efforts now are devoted to providing their ground forces with the equipment, the training, and encouraging their will to fight so that our campaign enabling them can be successful.’’
The comments come as the Islamic State appears to be surging, tightening its grip on Anbar province in Iraq and parts of Syria after US and Iraqi officials last month highlighted the group’s setbacks.
McCain, who is chairman of the Senate Armed Services Committee, on Sunday repeated his call to send US ground troops, including Special Operations forces, into Iraq.
“We need to have a strategy,” he said on CBS’s “Face the Nation.” “There is no strategy. And anybody that says that there is, I’d like to hear what it is. Because it certainly isn’t apparent now.”
Representative Mac Thornberry, the Texas Republican who heads the House Armed Services Committee, spoke on ABC’s “This Week” and emphasized the need for more and better intelligence.
“The other thing we’ve got to do is improve our intelligence capability,” he said. “We, I think, know less today than we knew five or six years ago about what terrorists around the world are doing for a variety of reasons.
“The key way to know what they’re doing, to prevent them from getting a nuclear, chemical, biological weapon, is to augment our intelligence capability,’’ Thornberry said, “and then you’ve got to act.”
Iraqi lawmaker Hakim al-Zamili, the head of the parliamentary defense and security committee, called Carter’s comments ‘‘unrealistic and baseless,’’ in an interview with the Associated Press.
‘‘The Iraqi army and police did have the will to fight IS group in Ramadi, but these forces lack good equipment, weapons, and aerial support,’’ said Zamili, a member of the political party headed by radical Shi’ite cleric Moqtada al-Sadr.
American officials say they are now sending antitank weapons to the Iraqi military. They also noted that Iraqi forces were not routed from Ramadi; they left of their own accord.
The retreating troops were frightened in part by a powerful wave of Islamic State suicide truck bombs, some the size of the one that destroyed the federal building in Oklahoma City two decades ago, the Associated Press reported, citing a senior State Department official who spoke to reporters last week on condition that he not be named.
‘‘The ISF was not driven out of Ramadi,’’ General Martin Dempsey, chairman of the Joint Chiefs of Staff, said last week. ‘‘They drove out of Ramadi.’’
Defense officials have said that the troops who fled Ramadi had not been trained by the United States or its coalition partners.
Still, the fall of Ramadi is reviving questions about the effectiveness of the Obama administration’s approach in Iraq, a blend of retraining and rebuilding the Iraqi army, prodding the Shi’ite-dominated government in Baghdad to reconcile with the nation’s Sunnis and bombing Islamic State group targets from the air without committing American ground combat troops.
Obama’s strategy is predicated on Baghdad granting political concessions to the country’s alienated Sunnis, who are a source of personnel and money for the Islamic State. But there has been little visible progress on that front.
Baghdad has continued to work closely with Shi’ite militias backed by Iran, which have been accused of atrocities against Sunnis, a religious minority that ruled Iraq for centuries until Saddam Hussein fell from power.
The United States has sought to reach out on its own to Sunni tribes and is training some Sunni fighters, but those efforts have been limited by the small number of American troops on the ground.
Carter said the US airstrikes cannot be a substitute for Iraqi ground forces willing to defend their country.
‘‘We can participate in the defeat of ISIL,’’ he said. ‘‘But we can’t make Iraq . . . a decent place for people to live — we can’t sustain the victory. Only the Iraqis can do that and, in particular in this case, the Sunni tribes to the West.’’
Any future political arrangement would have to grant significant local autonomy to the three main groups— Sunnis, Shi’ites and Kurds. But the Obama administration has continued to pursue a ‘‘one Iraq’’ policy, routing all assistance through Baghdad.
In pulling back from Ramadi, the Iraqi troops left behind large numbers of US-supplied vehicles, including several tanks, now presumed to be in Islamic State hands.
Over the past year defeated Iraq security forces have repeatedly left US-supplied military equipment on the battlefield, which US planes have targeted in subsequent airstrikes against Islamic State forces.
The Pentagon last week estimated that when Iraqi troops abandoned Ramadi, they left a half-dozen tanks, a similar number of artillery pieces, a larger number of armored personnel carriers and about 100 wheeled vehicles like Humvees.
The list of air strikes overnight in Iraq announced by the Pentagon on Sunday included four near Ramadi that destroyed 19 armored vehicles. It was unclear whether any of those had been recently abandoned by the Iraqi army.
Material from the Associated Press was included in this report.