ERBIL, Iraqi—The U.S.-backed Syrian Democratic Forces launched “the Wrath of the Euphrates” campaign on Saturday to isolate the so-called Islamic State’s Syrian capital, Raqqa.

The Turkish government, which had wanted to delay the Raqqa campaign until after the city of Mosul is taken in Iraq, which could be a matter of months. But the U.S.-led coalition did not want to lose the momentum.

The situation is complicated by the fact that many of the SDF’s fighters are members of the Kurdish YPG or People’s Protection Brigades, which the Turks consider an appendage of the PKK guerrillas they are fighting on their home turf.

But the fighters of the SDF/YPG have been some of the best and most reliable combatants working with the United States against ISIS. If they manage to take the initiative on the battlefield again, that will make it harder for the Turks to block them or the Americans to back away from them.

“We call on our dear people of Raqqa to distance themselves from Daesh [ISIS] sites within Raqqa and to head towards areas that will be liberated,” the SDF said in a statement on Sunday

The SDF announced its forces have attacked ISIS from two sides: from the general direction of Suluk, and from the town of Ayn Issa, both of them more then 55 kilometers (35 miles) north of Raqqa city.

The SDF said they have already advanced 10 kilometers in both fronts, and taken five villages since Saturday evening.

Local journalists embedded with SDF forces say the operation is probably going to take a lot of time and will focus on the countryside of Raqqa first. This offensive has been long anticipated.

“Come, come, the operation for Raqqa will start, we are getting ready,” a Kurdish fighter from Hasakah told The Daily Beast by WhatsApp on 25 October. On 3 November, he told me again the operation was about to start. “Why you are not coming?”

But as The Daily Beast reported last week there have been a number of stumbling blocks.

It is expected to take months before local forces actually enter the city, Sunday’s announcement marked the start of the initial phase of the war and the latest effort by Washington to shape the messaging of the war against ISIS.

A slew of headline-grabbing announcements in the last month suggesting ISIS’s imminent collapse definitely are not part of that messaging, defense officials insist. Rather, the SDF/YPG Kurdish forces in Syria and the Iraqi forces next door that are leading the ground attack on ISIS’s two biggest cities are setting the battle timelines on their own, according to these officials.

At the same time, the administration has said for months it was keen to see the move on Raqqa and Mosul take place simultaneously.

“Waiting for Mosul to be finished was never the vision,” one senior U.S. defense official explained Sunday.

Iraqi forces began moving toward Mosul last week, but those troops only entered the city last week, and there is every indication hat securing the entire metropolis of more than a million people will be a long, hard slog.

The fight for Raqqa is not nearly as far along. Sunday was the “move toward the isolation phase” of the battle for Raqqa, the defense official explained to The Daily Beast: local forces are to surround the city and cut off ISIS’s ability to get weapons, supplies, and reinforcements.

The isolation campaign for Mosul took eight months. Officials said that Raqqa won’t be as long at that, but, still, will likely be a months-long effort. Air Force Col. John Dorrian, a spokesman for the U.S. effort, reportedly called Sunday’s announcement the start of an “extended timeline.”

“From isolation, we can move to the assault phase, when forces enter the city,” the as one defense official told the Daily Beast.

Defense officials have said roughly 6,000 Kurdish forces, from the SDF/YPG, will surround the city. In addition, the U.S.-led coalition plans to ramp up its airstrikes.

But even as the Kurdish forces announced the start of the isolation campaign, what forces will actually enter Raqqa when the time comes remains unclear. But Turkey, a U.S. NATO ally, has said it would not allow the YPG, which it considers a terrorist group, to take Raqqa.

The U.S. currently is negotiating with the Turks about the Raqqa operation but has yet to reach an agreement about the role of the Kurds, who hope their effort will lead the U.S. to recognize their autonomous region inside Syria.

Meanwhile, Army Lt. Gen. Stephen Townsend, the commander of the U.S. effort in Iraq and Syria, said local Arab forces are still being recruited and trained for the eventual Raqqa campaign.

“It’s a complicated situation, not only militarily but politically,” the defense official said.

And the Americans, Kurds, Arabs and Turks are not the only ones involved.

French officials are worried that ISIS will actually gain strength in Syria as ISIS fighters fleeing from Mosul fall back across the border. So the French have been pressuring the U.S. to do something in Raqqa, since all the attacks in France, including the one in Paris that killed over 130 in November last year, were planned from Syria. Coalition officials say most of the ISIS external operations in Europe are planned from Raqqa, and many French foreign fighters are based in Raqqa. The Raqqa operation would also counter Russian government media that spreading propaganda that there is a U.S. deal with ISIS allowing it to relocate to Syria by leaving a road open from Mosul to Syria. Nawaf Xelil, a former spokesperson of the Democratic Union Party (PYD), the political arm of the YPG, who now leads a Kurdish research center in Europe told The Daily Beast, that 30,000 fighters are participating in the Raqqa operation. “The Syrian Democratic Forces, YPJ, YPG, and forces from Raqqa, started an operation with the strategic goal [to take Raqqa]. This is important for Raqqa, Turkey, Kurds, and the future of Syria,” he said. “ [Raqqa] is symbolic, it’s the capital of ISIS, and Kurdish [Yezidi] women and mothers were sold there, it was a center of oppression.”

“The first step is to isolate the city. Then it [Raqqa city] will be freed by all the forces, and as you know there are many local groups fighting alongside the SDF,” Xelil said.A U.S. official in the region told The Daily Beast that, yes, the first phase is to isolate, and then the second phase is to capture Raqqa—but the official said it would all be in one operation like the capture of Manbij over the summer.The number of fighters participating in Raqqa is twice as big as the number of forces that took Manbij, but follows a similar model, in which the SDF said fighters who came from Manbij would be the main force retaking the city. The SDF says only the “sons of the area” from Raqqa will participate as part of the Wrath of Euphrates Operations Room. Murat Yesiltas, an expert at the pro-government think tank SETA in Turkey told The Daily Beast that the operation probably has not won Turkish backing at this point.

“Off course not,” he said, “because Turkey knows very well that the SDF is an artificial project which means the real actor behind the SDF is PKK/YPG [Kurdistan Workers Party]. Therefore I don't think Turkey will support the operation.” However, Ragıp Soylu, the Washington-based correspondent for the Daily Sabah believes that Turkey could accept the operation. “My understanding is Turkey won't make a big problem out of Raqqa operation unless they [the YPG] enter the city. The signals coming out of Turkish-American bilateral meetings show that Turkey is somewhat okay with the isolation of Raqqa.” "We'll continue to talk with Turkey about its role in the eventual seizure of Raqqa, but we're proceeding now with the operation according to our plan," U.S. Defens Secretary Ash Carter said last week during a news conference. U.S. officials say Turkey was informed about the operation. “Everything we do with the SDF is shared with the Turks beforehand,” a coalition official said. “We always seek to make our SDF operations palatable to them and explain why we are doing Operation X.” The U.S. apparently had wanted to include Turkey in the Raqqa operation, but Kurdish officials, for their part, told the U.S. that the Kurdish-led SDF forces would not participate if there were Turkish involvement. The Turks “have no desire to send their own forces deep into Syria to Raqqa, and given that they won’t, the SDF is the only other option, and the Turks say they won’t support a SDF operation,” said a U.S. official.

So, it’s expected Turkish ground forces or Turkish-backed rebels will not be involved on the ground, but the U.S. will keep Turkey informed.

“The Turks will have visibility over the operation alongside our people,” he added.

Moreover, Turkish-backed rebels may not be capable of doing the Raqqa operation. They are still barely holding on what they have taken in the Euphrates Shield operation in Northern Aleppo, having lost several villages to ISIS-counter attacks.

Until now the Turkish-backed rebels there have not even yet captured the town of al Bab (despite claims to the contrary), which appears to be another reason Turkey wanted to delay the Raqqa operation. The Turkish-backed rebels are in the unenviable position of fighting ISIS, the Kurds, and Assad in Aleppo province at the same time. The main goal of the Turkish operation launched in was to prevent the Kurds from uniting their local administrations in Efrin and Kobani by capturing territory in Northern Aleppo and creating a Kurdish federal region on Turkey’s borders. So, for all these reasons, “The SDF[YPG] is the best indigenous partner of the U.S.-led coalition to proceed with these shaping operations toward Raqqa,” says Nicholas Heras, a Washington-based Middle East researcher at the Center for a New American Security.

“The U.S.-led Coalition wants to maximize the pressure on ISIS while the Mosul operation is progressing forward. This campaign on Raqqa is not meant to seize the city in one quick battle. The coalition wants to take as much territory around the city of Raqqa as possible as the Mosul operation proceeds,” he added.

Just how long will this go on?

“I don't expect immediate miracles, but this will be a slow containment operation followed by finally choking all the remaining logistical support routes,” Michael Stephens, the head of the Royal United Services Institute –Qatar, told the Daily Beast. Along the way, “I don’t think the SDF can take Raqqa without a significant amount of arming and a lot of air support,” he said.

Less politics and intrigue within the anti-ISIS itself might be helpful as well.