Having reached a deal with the Turkish government to set up a buffer zone inside Syria, ostensibly to combat the Islamic State in Iraq and Syria (ISIS), official Washington has begun debating the rules of engagement for US military forces to intervene against the Syrian military.

The proposal to seize a strip of land on the Syrian-Turkish border (Turkey’s official news agency has published a map showing it to be 65 miles wide and 25 miles deep) has been accepted by the Obama administration as part of an agreement allowing US warplanes to use Turkey’s Incirlik Air Base to carry out airstrikes against ISIS targets.

Turkish officials, who have advocated the seizure of Syria’s northern border area for at least the past four years, refer to a “safe zone”—effectively a no-fly zone—which it says will be protected by Turkish military force. US officials have been more circumspect, insisting that Washington’s goal is only to create an “ISIS-free” zone.

Semantical differences aside, however, the agreement lends US backing to an intervention proposed by the Turkish regime with the clear aim of ramping up the Western-backed war for regime change that has devastated Syria since its onset in 2011.

Administration and Pentagon officials have indicated that the precise nature of the proposed zone and who will secure it are issues still under discussions between Ankara and Washington.

“In terms of what exactly it looks like and how it will look and what the modalities are, that’s what we have to work out with them,” said one official—referring to the Turks—during a background call with the media Tuesday.

It is acknowledged in official circles, however, that the creation of such a zone will lead to a significant escalation of the US intervention in Syria. Frederic Hof, the Obama administration’s former ambassador and special adviser on “Syrian transition,” told the Christian Science Monitor that Obama, “in his 18 months or so remaining in the White House definitely wants to see some progress on Syria.”

He added, “The Washington-Ankara initiative may be far more than a chapter in a ground war against ISIS.”

The issue is complicated by the divergent tactical aims of the two NATO allies. While both the US and Turkey now claim to be united in a common struggle against ISIS, Turkish actions have clearly demonstrated that destruction of the Islamist militia is not its main goal.

Since launching attacks in Iraq, Syria and within Turkey itself, all in the name of a renewed struggle against “terrorism,” it has concentrated its fire not on ISIS, but on the Kurdish separatist guerrilla movement in Turkey, the PKK (Kurdish Workers Party), which has suffered heavy aerial bombardment of its bases across the border in northern Iraq, and its Syrian counterpart, the YPG (People’s Protection Units), whose forces have come under artillery barrages.

These Kurdish movements have constituted the main armed opposition to ISIS in northern Syria and, in the siege of Kobane, just south of the Turkish border, fought with air cover provided by US warplanes. Now, the US State Department is providing a tortured defense of the Turkish attacks on the grounds that the PKK is formally classified by the department as a terrorist organization, while the YPG is not.

NATO also provided a tacit endorsement of the anti-Kurdish campaign launched by Ankara. Following a 90-minute emergency meeting Tuesday, the US-led military alliance declared itself in “solidarity” with Ankara in the struggle against “terrorism,” without bothering to distinguish between ISIS and the Kurdish groups. Germany and some other European powers, however, have viewed the Turkish assault on the Kurds with growing concern, fearful that it will only ignite a broader war in the region.

The Turkish regime of President Recep Tayyip Erdogan is determined to break the grip of Kurdish forces in northern Syria, fearing that it will become an autonomous Kurdish territory that could spread into predominantly Kurdish areas of Turkey as well. It will certainly veto any proposal to use these forces to secure the so-called buffer zone.

The only other anti-ISIS forces in the area are a collection of Islamist militias, dominated by the Al Qaeda-affiliated Al-Nusra Front, which have long operated with barely concealed Turkish government support as well as covert backing from the American CIA, which established a station in southern Turkey to funnel in arms and fighters.

Then there are the US-armed and trained “moderate” Syrian fighters. While the Obama administration allocated $500 million nearly a year ago for the purpose of fielding a force of 15,000, US Defense Secretary Ashton Carter was compelled to admit to the Senate Armed Services Committee earlier this month that it had succeeded in producing less than 60 fighters thus far. According to one report, this meager band was loaded onto pickup trucks, sent back into Syria and never heard from again.

This has not stopped advocates of a more robust US intervention in Syria from waging a heated debate on what the US military should be prepared to do to support these mercenaries.

On Tuesday, Pentagon spokesman Lt. Col. Joe Sowers acknowledged, “The US is committed to the success of the personnel we will train. We are still considering the full complement of support we might provide to [these] forces.”

The web site Defense1 reported that during Defense Secretary Carter’s recent testimony, he expressed doubt about the “legalities” of the US military intervening against Syrian government forces to protect the mercenaries it has armed and trained.

This prompted calls from both Democrats and Republicans for an amendment of the Authorizations for the Use of Military Force (AUMFs), passed in 2001 and 2002 to launch the “global war on terror” and the invasions of Afghanistan and Iraq, to expand their remit to Syria.

Under these conditions, the small band of mercenary “rebels” trained by the Pentagon would serve merely as a catspaw, providing the pretext for direct US military intervention to topple the Syrian government of President Bashar al-Assad.

While endorsed by Washington, Turkey’s punitive punishment of the Kurds has been condemned elsewhere in the Middle East as well as in Turkey itself.

The Iraqi government condemned the air strikes against PKK camps in northern Iraq as “a dangerous escalation and an assault on the Iraqi sovereignty.”

In Turkey, Selahattin Demirtas, chairman of the HDP, the new pro-Kurdish Party which won 13 percent of the vote in the last election, depriving Erdogan’s ruling AKP of its majority, denounced the proposal for a “safe zone” as a ploy. “Turkey doesn't intend to target IS with this safe zone,” he said. “The Turkish government was seriously disturbed by Kurds trying to create an autonomous state in Syria.”

Demirtas was quoted by the Syrian news agency SANA as telling an HDP meeting that the terrorist attack attributed to ISIS that killed 32 people—most of them members of a leftist youth movement—in Suruc, near the Syrian border, was actually the work of government agents bent on providing a pretext for military action.

SANA quoted Demirtas as charging that a “Special Gladio” organization, affiliated to the Turkish presidential palace, was behind the terrorist bombing. He was referring to the clandestine anti-communist units created in the postwar period under the auspices of NATO and the CIA. Gladio’s Turkish branch has since morphed into the ÖKK, or Special Forces Command.

Syria’s Foreign Ministry, meanwhile, addressed letters to the United Nations Security Council and the UN Secretary-General denouncing the new Turkish military actions, charging that the Turkish government is “directly responsible for the shedding of Syrian blood and the humanitarian suffering of millions of Syrians inside and outside Syria” through its material support for terrorist groups inside Syria and its allowing thousands of “foreign fighters” to enter Syria from Turkish territory.

The scale of this humanitarian catastrophe caused by the Western-backed war for regime change in Syria was spelled out Tuesday in testimony before the UN Security Council by Stephen O’Brien, the UN Under-Secretary General for Coordination of Humanitarian Affairs. He reported that in addition to the estimated 220,000 killed in the conflict, some 12.2 million Syrians are now in need of humanitarian assistance. He added that the fighting had forced over one million Syrians from their homes so far this year—many for the second or third time—joining the 7.6 million people that had already been internally displaced by the end of 2014.

Noting that the UN’s humanitarian response plan was only 27 percent funded, O’Brien called Syria “the most acute, unrelenting and shameful blot on the world's humanitarian conscience.”