WASHINGTON — Pentagon officials have concluded that hundreds more trainers, advisers and commandos from the United States and its allies will need to be sent to Iraq and Syria in the coming months as the campaign to isolate the Islamic State intensifies.
In meetings with President Obama’s national security team in recent weeks, military officials have told the White House that they believe they have made significant progress in the fight against the Islamic State in both Iraq and Syria, administration officials said. But to deal a lasting blow to the extremist Sunni militancy, also known as ISIS and ISIL, they believe that additional forces will be needed to work with Iraqi, Kurdish and Syrian opposition fighters on the ground in the two countries.
In the past, the Pentagon’s requests for additional troops in both Iraq and Afghanistan have been met with skepticism by Mr. Obama, and his aides have said he has resented what he has regarded as efforts to pressure him. But the rise of the Islamic State has alarmed the White House, and a senior administration official said Thursday that the president is willing to consider raising the stakes in both Iraq and Syria.
The United States already has about 3,700 troops in Iraq, counting a small handful of Special Operations forces on the ground in Syria. One official said that he did not anticipate that number increasing to more than 4,500 over time, and even that increase, the official said, could come incrementally, much as the deployment of the 3,700 American troops occurred over the period of a year and a half. During that time, the White House and the Pentagon have taken pains to avoid describing the deployments as combat troops, instead calling them special operators, trainers and advisers.
Defense Secretary Ashton B. Carter, in an interview last week with CNN in Davos, Switzerland, emphasized the limited role he anticipated American forces to play. “We’re looking for opportunities to do more,” Mr. Carter said, but added, “We’re not looking to substitute for local forces in terms of governing the place and policing the place.”
The Pentagon’s desire to expand the military presence on the ground comes as the American public remains skeptical of the United States’ getting more deeply involved in another conflict in the Middle East. Polls have shown that Americans are not convinced the Obama administration has a plan to defeat the Islamic State, which has maintained control of nearly all the large cities it took over in 2014.
“With more capacity, you can do more,” said Derek Chollet, a former assistant secretary of defense in the Obama administration. But, he added, “The challenge has always been what is that line between enabling and owning, and that’s something the president will be focused on.”
Recent victories by Iraqi security forces and Syrian opposition groups — aided by airstrikes from the American-led coalition — have made Pentagon officials, including Mr. Carter and the chairman of the Joint Chiefs of Staff, Gen. Joseph F. Dunford Jr., more optimistic about the effectiveness of Iraqi forces if they were coached and trained by Americans.
With the liberation of the Iraqi city of Ramadi last month, coupled with recent gains in northern Syria, senior military leaders say that the war effort can now focus on isolating — and then liberating — the Islamic State-held cities of Mosul in Iraq, and Raqqa in Syria. “The reason we need new trainers or additional trainers is because that’s really the next step in generating the amount of combat power needed to liberate Mosul,” Col. Steve Warren, the spokesman for the American military in Baghdad, said last week. “We know we will need more brigades to be trained, we’ll need more troops trained in more specialties.”
The United States has had little success in persuading allies to provide more troops. But Mr. Carter and General Dunford do not want the United States to be the only source of more forces. With ISIS posing a threat to European countries, they are trying again.
“I have personally reached out to the ministers of defense in over 40 countries around the world to ask them to contribute to enhancing the fight against ISIL — more special operations forces, more strike and reconnaissance aircraft, weapons and munitions, training assistance, as well as combat support and combat service support, “ Mr. Carter said in Paris last week. “I expect the number of trainers to increase, and also the variety of the training they’re giving,” he said in a briefing with reporters earlier in the trip.
At the end of last year, Mr. Carter sent letters to many of his counterparts, laying out for them how they could do more. “We deeply appreciate Italy’s commitment to this fight; however, much work is yet to be done,” Mr. Carter said in one letter, dated Dec. 1, to the Italian defense minister, Roberta Pinotti. The letter was obtained by Wikilao, a Rome-based security website.
Mr. Carter said the Italians, who have led the training of Iraqi police forces used to hold cities reclaimed from the Islamic State, could help the coalition by sending more trainers and other personnel to help with surveillance, intelligence and reconnaissance. The coalition also needs help with search and rescue teams and more offensive military support, he said.
Mr. Carter will hold a meeting next month in Brussels with the 27 countries that have participated in the military efforts to defeat the Islamic State. Among those countries that have been invited to the meetings are several Arab ones that had initially participated in the campaign but have since contributed little. Mr. Carter has singled them out, saying that it is time for them to become more involved. “Every nation must come prepared to discuss further contributions to the fight,” Mr. Carter said last week.
Asked for comment on Wednesday night, Peter Cook, a spokesman for the Pentagon, said commanders were still studying whether they would need more American forces. “Once our commanders on the ground have a clearer picture of the capabilities required to accelerate the campaign, as well as the contributions from our coalition partners, we will have a better idea what if any additional resources may be needed,” he said.