Now that the anti-ISIS coalition has struck Raqqa in Syria, it must seriously consider the Kurds as its most effective on the ground partners. The Obama administration needs local partners in Iraq and Syria to fight against the jihadist group, the Islamic State in Iraq and al-Sham (ISIS, ISIL, or the Islamic State) if it hopes to maintain any gains resulting from its attacks on ISIS positions. A spokesperson of the main Kurdish armed group in Syria highlighted the importance of Kurdish assets. “Whoever wants to destroy ISIS should take YPG into consideration. Let me say clearly that any strategy in Syria without YPG is doomed to fail,” the People’s Protection Units (YPG) spokesperson Polat Can said in our interview with him. Given the Kurds’ extensive experience and professionalism, they represent the best the best chance to revitalize a beleaguered Syrian resistance and help President Obama achieve his objectives.

In his September 10 speech, President Obama ruled out the Assad regime as a partner in fighting ISIS and emphasized strengthening the Syrian opposition. “We must strengthen the opposition as the best counterweight to extremists like ISIL, while pursuing the political solution necessary to solve Syria’s crisis once and for all,” he said. While admirable that the president choose not to work with a man whose preferred strategy involves bombing his own civilian population, it leaves a dearth of effective partners on the ground. However, in Syria—just as in Iraq—cooperation between Kurds and Arabs could play a key role in eliminating ISIS. US Chairman of Joint Chiefs of Staff General Martin Dempsey recognized the fact that Kurds constitute an important part of Obama’s new strategy to fight ISIS.

Although Iraq has witnessed firsthand the effects of ISIS-induced instability, neighboring Syria has suffered far more with the advances and atrocities of the extremist group. ISIS has succeeded in wiping out many Syrian nationalist armed groups that comprise the bulk of moderate anti-Assad opposition. Both the moderate Free Syrian Army (FSA) and the Kurds have faced attacks by ISIS, leading to incredibly large refugee flows into Turkey. Nonetheless, the Kurdish YPG forces— the armed wing of the Kurdish Democratic Union Party (PYD) in Syria—have successfully fought ISIS and won most of its battles in both Iraq and Syria. Not only was the YPG an asset in the rescue operation for thousands of Yezidis fleeing from Iraq’s Sinjar, it also secured a wide area in northern Syria from the Kurdish city of Afrin to Yarubiya, a town border to Iraq, despite the extremist push against Kurdish villages. These regions maintain relative stability compared to other parts of Syria, allowing Kurds, Arabs, and Christians to live peacefully together, thanks in large part to the ability of the YPG to keep a modicum of security.

Western diplomats have traditionally been reluctant to meet the PYD for their ties to the Kurdistan Workers Party (PKK), viewed as a terrorist group in the United States and Turkey. After successful operations against ISIS extremists, however, both countries have begun reevaluating their positions towards it. The Wall Street Journal reported that US officials recognize the fact that Kurdish fighters in Syria may play a critical role in the campaign against ISIS, and have conducted talks with Syrian Kurds. The success of the YPG also prompted Turkish journalist Amberin Zaman to write about how the fight against ISIS has given the YPG and the PKK more legitimacy.

For their part, the Syrian Kurds have not only expressed interest and enthusiasm in pursuing Obama strategy against ISIS, they have already laid the groundwork for cooperation with Syrian nationalists. In an interview with Voice of America (VOA), YPG Spokesman Polat Can said, “We are the most experienced military force fighting against IS, and we are willing to actively participate in the international coalition. We are currently meeting many countries on this issue including with those who are decision makers.” As the YPG continue its fight against ISIS on several fronts, it hosted a former rival on August 22. FSA Colonel Abdul Jabbar al-Oqaidi sought to mend fences with the Kurds by meeting YPG commander with General Commander of YPG Sipan Hemo in the Kurdish city of Afrin, north of Aleppo. Al-Oqaidi, the former head of the FSA’s military council in Aleppo, initially angered the Kurds by fighting jointly with Islamist groups against the Kurds in Aleppo. The FSA said it attacked the YPG for supporting Assad. Kurds allege this led to the killing of nineteen Kurdish civilians and the kidnapping of at least 400 others by the various rebel groups.

But in January last year, alliances started to change, when the Free Syrian Army clashed with ISIS, and lost huge swaths of territory in Syria, including Raqqa and the oil fields in Deir Ezzor. This led new cooperation between rebel groups and the Kurds, resulting in an agreement between the YPG and the Ahl as-Sham operation room in April last year to fight ISIS in Aleppo, and to cooperate against Assad. On August 22, al-Oqaidi and an FSA-delegation apologized for the FSA’s past mistakes, saying that Kurds, Christians, and Arabs, should work for the overthrow of the Syrian regime. “We want to work with the Syrian National Coalition (SNC) and the FSA if they accept the rights of Kurdish people and correct past mistakes,” Hemo said in a video. In an exclusive interview, the Defense Minister of local Afrin Canton government Abdo Chilo, who took part in the meeting between the YPG and the FSA in Afrin, also told the Atlantic Council that the FSA wants to open a new page with the Kurds. “We told him we accepted his apology and we valued his visit. He realizes the power of YPG and wants closer relations with us, something we have long desired as well.”

The Kurds appear ready to fight alongside any secular group that will work for a pluralistic and democratic Syria against ISIS and the Assad regime. “We value Oqaidi’s visit and his request of help from YPG. It shows his willingness to work and create something good. We are ready to form a joint front with FSA and work against IS thugs and the brutal Assad regime,” Chilo added. YPG spokesman Polat Can told Turkey’s daily Radikal that they are ready to work with anyone who is willing to fight against ISIS. “It has been over two years that we have been fighting against ISIS and like-minded extremist groups. We are keen on collaborating with moderate that respect to democracy, human rights and accept our national rights as Kurds.”

This historic meeting signifies a major starting point for effective cooperation against ISIS as well as the Assad regime. The meeting led to the formation of a new joint FSA-YPG operations room named “Euphrates Volcano” on September 10 in Kobane, which will carry out operations in areas surrounding Kobane, including the ISIS-stronghold of Raqqah. One day after its formation, the joint operation room carried out its first attack against ISIS in Qara Qawzak. Abdurrahman Saleh, a spokesperson for ISIS, confirmed in our interview with him an alliance between Syrian anti-Assad rebels and Kurds, but suggested it to be a local alliance rather than a cohesive policy. “Some battalions of al-Tawheed brigade in Aleppo cooperate with the YPG against ISIS, but I do not know if this is a general decision, or a specific case. It may be a local agreement, rather than an overall strategy,” he said.

The new rebel alliance between the Kurds and the FSA could provide a determining factor to stop the expansion of the ISIS caliphate. If the FSA and the YPG can maintain a joint front, it will likely have a major impact on the success of fight both the militant group and the Assad regime in the longer run. The YPG, with its experienced and skilled fighters and strong popular support can provide a morale boost for the secular and moderate Syrian opposition and be a determining factor in preventing ISIS expansion in Syria. For Obama and the anti-ISIS coalition, keeping the Kurds incentivized to be their boots on the ground will be the key to fighting this war.

Wladimir van Wilgenburg is an analyst of Kurdish politics for the Jamestown Foundation and a contributing writer for Al-Monitor.

Mutlu Civiroglu is a Washington, DC based-journalist and Kurdish affairs analyst focusing on Syria and Turkey. He has been closely monitoring YPG’s fight against IS and other jihadist groups. You can follow him on Twitter @mutludc.