Is the tide turning against Islamic State?

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Is the tide turning in Iraq against the self-described Islamic State, or are events there just the normal ebb and flow of war?

US defense officials said yesterday that the Islamist group’s advances in Iraq had been stalled or reversed, and held out the possibility that US ground forces may be called on to assist an Iraqi Army that was no longer fleeing the battlefield. Today, Iraqi security officials said that IS militants had been driven from Baiji, Iraq’s largest refinery, which they had captured in a stunning summer offensive.

The gains also followed by just one day the release online of an audio recording of the IS leader, Abu Bakr al-Baghdadi, in which he urged his followers to “erupt volcanoes of jihad everywhere” and disparaged US plans to send additional soldiers to Iraq.

The Associated Press, citing two Iraqi security officials it reached by telephone in Baiji, reported Friday that Iraqi troops backed by Sunni militias had pushed the IS from its last strongholds in the town and had hoisted the Iraqi flag over the refinery. The officials said bomb squads were working to clear booby-trapped houses and bombs planted on the roads.

State Iraqi television also reported the "liberation of Beiji," quoting the top army commander there, Gen. Abdul-Wahab al-Saadi.

The two officials said fierce battles were fought early on Friday around the refinery and that government warplanes strafed Islamic State positions around the facility on the northern edge of the town. The refinery's capacity of some 320,000 barrels a day accounts for a quarter of Iraq's refining capacity.

In Washington, Gen. Martin E. Dempsey, chairman of the US Joint Chiefs of Staff, told the House Armed Services Committee Thursday that Iraqi troops' performance is improving, but that US troops might have to help them clear larger cities, such as Mosul, that are occupied by the IS militants, The New York Times reported.

“I’m not predicting at this point that I would recommend that those forces in Mosul and along the border would need to be accompanied by U.S. forces, but we’re certainly considering it,” General Dempsey said. Defense officials said that American Joint Tactical Attack Controllers could be used to call in airstrikes from tactical positions on the ground, most likely behind Iraqi forces. The tactical attack controllers often deploy in positions like hills and other high terrain so they can see operations and call in strikes.

General Dempsey did say that he did not anticipate expanding the American military presence in Iraq beyond what he called a modest force. “I just don’t foresee a circumstance when it would be in our interest to take this fight on ourselves with a large military contingent,” he said.

The reported Iraqi gains were not the only apparent setback for the IS forces.

Islamic State controls large sections of northern Syria and Iraq and just this week broadened its alliances throughout the Middle East, including an apparent rapprochement with an Al Qaeda affiliate in Syria and a pledge of allegiance from Ansar Bayt al-Maqdis, which has been attacking Egyptian military forces in the Sinai Peninsula.

But in northern Syria, along the border with Turkey, a months-long IS siege of Kobane has apparently stalled since Iraqi Kurdish peshmerga fighters joined the city's Kurdish defenders. The siege had driven more than 200,000 mostly Kurdish residents into Turkey, and drawn the attention of the US-led, anti-IS bombing campaign, which reportedly has killed hundreds of IS fighters in Iraq and Syria in recent weeks.

Mr. Baghdadi’s recorded speech, meanwhile, seemed to put to rest rumors about his fate after a weekend airstrike against a column of IS vehicles in northern Iraq. The speech made reference to the Ansar Bayt al-Maqdis pledge, which occurred Monday, and was distributed online in three languages, the Times reported.

With characteristic bluster, Mr. Baghdadi exhorted Muslims throughout the Middle East to rise up against “the agents of the Jews and crusaders, their slaves, tails and dogs.” He declared, “We see America and her allies stumbling between fear, weakness, inability and failure.”

His forces have seized large areas of Syria and Iraq, and an American-led coalition is waging a campaign of airstrikes against them. Last Friday, Mr. Obama announced plans to deploy 1,500 additional soldiers to Iraq, effectively doubling the number assigned as advisers to help the Iraqi Army beat back the militants.

Mr. Baghdadi scoffed at that plan. “Here is Obama, who has ordered the deployment of 1,500 additional soldiers under the claim that they are advisers because the crusaders’ airstrikes and constant bombardment — day and night — upon the position of the Islamic State have not prevented its advance, nor weakened its resolve,” he said in the audiotape.