With the seizure of Marea, the SDF — spearheaded by the YPG — controls the Jarablus-Munbij-Bab line, exerting pressure from the east and west on the IS presence around Raqqa. Now we have the unusual situation of US air support for the YPG in the east and Russian air support in the west.

This development also meant Russian soldiers are operating as forward air controllers in the field alongside the YPG. YPG units, in alliance with Syrian Democratic Forces (SDF), also seized Marea and are continuing their eastward advance. The YPG, which liberated Tell Abyad from Islamic State (IS) control in June with US air support, is now expanding its territory to Afrin’s east, this time with Russian air support, which naturally frustrates Ankara.

In this surge of activity, new developments demand attention. One such development is the YPG advance to the east. Turkish Prime Minister Ahmet Davutoglu declared that Turkey will not allow the fall of Azaz, but the YPG captured Tell Rifaat just south of Azaz with the first-ever overt Russian air support.

Syrian President Bashar al-Assad's forces, supported by Russian warplanes, are trying to control critical supply routes between Turkey and Aleppo. Ankara has declared the Kurdish People's Protection Units (YPG) a terrorist organization because of its organic ties to the Kurdistan Workers Party (PKK) and expansion of its Afrin canton in western Kurdistan northwest of Aleppo.

Developments in Syria have picked up speed rapidly in the past two weeks, and the situation is only becoming more complicated.

The YPG now has to make a critical decision: Will it continue with US or Russian support? It is critical, because if the YPG opts for cooperation with Russia, it can expand the Afrin canton eastward and link it with two other Kurdish cantons, Kobani and Jazeera. This of course will create a Kurdish corridor between Turkey and the rest of predominantly Sunni Syria. This will be a nightmare scenario for the Sunni bloc led by Ankara and Saudi Arabia and supported by Qatar and Bahrain.

Or the YPG — instead of expanding on an east-west axis under US guidance — can focus on the IS "capital" of Raqqa. If this happens, we will know that the YPG has the full backing of the SDF. This will require sidelining the Sunni armed opposition, particularly around Aleppo, and reaching some sort of understanding with Assad's forces and the Russians. Many believe that this is what the United States is trying to achieve now.

The question is whether the YPG can manage to sustain simultaneous cooperation with the United States and Russia. This is what Ankara is carefully watching. Ankara tends to think the YPG will opt for Russian cooperation and thinks of the YPG as a Russian subcontractor in Syria. Ankara resents the US disregard for this view.

There are officials in Ankara who consider the YPG’s attempt to cooperate simultaneously with the United States and Russia a tactical and provisional move that cannot be sustained for long and which the YPG must be called to account for at some time.

Ankara thinks there are two ways it can return to Syria's playing field, from which it was excluded after a Turkish F-16 shot down a Russian Su-24 warplane Nov. 24.

The first is with a "Sunni anti-IS air force" led by Ankara. If it can persuade Washington, Ankara wants to use this Sunni air force inside Syria with the participation of Saudi Arabia and Qatar. At the moment, six Saudi F-15s are in joint training with Turkish pilots at Turkey’s air combat training center in Konya.

Their training includes joint air operations and air-ground coordination. At the end of February, another 20 Saudi F-15s are expected at Incirlik Air Base. There are also reports that Qatari planes are already at Incirlik but have yet to become operational. Can the Sunni air force Turkey is trying to put together with Saudi Arabia and Qatar carry out joint operations in Syria? The United States will have to answer this question, because the Sunni air force will be Plan B in the hands of the United States in its strategic negotiations with Russia. This force is also needed for anti-IS attacks against Raqqa and Deir ez-Zor. Ankara and Riyadh are impatiently awaiting US approval to attack IS, which will open the gates of Syria to them.

Another instrument Ankara uses to influence the developments in Syria is Turkey's 155 howitzers deployed on the borderline near Kilis. These guns can easily reach Azaz and Marea, which are roughly 10 miles from the border. To start with, Ankara is planning to deploy more howitzer batteries along the entire border stretch controlled by the Kurds' Democratic Union Party (PYD) at Kobani, Tell Abyad and Qamishli. This will provide Ankara with artillery coverage 25 miles deep inside Syria. But the UN Security Council's recent call on Turkey to stop firing artillery inside Syria may well disrupt this plan.

This is not yet an official UN Security Council resolution, but should Ankara continue with artillery fire, it is likely to cause a serious debate.

The second element to Ankara’s return to the Syrian playing field is the position of Saudi Arabia. In my conversation last week with two Saudi academics, I noted their reference to Russian operations in Aleppo as "Russia's new Afghanistan." Both called for immediate delivery of Stinger missiles and SA-7 portable, short-range, surface-to-air anti-aircraft missiles (also known as MANPADS, or man-portable air defense systems), as was done with the anti-Russian fighters in Afghanistan. Both agreed this is the only way to eliminate Russian and Assad air force pressure and save Aleppo. The academics also agreed that first Turkey and then the United States have to be persuaded to deliver those weapons. If at some point in the near future we read news of Russian warplanes or helicopters shot down over northern Syria, we will know that the United States and Turkey have agreed with Saudi Arabia's demand.

While developments in Syria continue at an amazing pace, sadly Ankara is caught unprepared and is trying to catch up with events in hindsight. Ankara and its supporting media attribute this lack of preparation either as "ploys by global forces" or their collaborators in Turkey.

One wonders why Turkey doesn't assess the field developments in Syria accurately and wisely. There appear to be three basic structural flaws:

The first is using Syria as a Turkish domestic consumption commodity. Turkish decision-makers prefer to appeal directly to the people in official ceremonies and at other public gatherings. Their intention is to avoid discussing field developments, but to create a perception of victory in the minds of the Turkish electorate.

The second flaw regarding why Ankara can’t properly assess the realities in Syria and display the prerequisite flexibility is the tendency of mid-level officials and intellectual/academic circles to voice what they think the situation should be, rather than seeing the way things actually are.

The third flaw is Ankara's viewing of the Assad regime and the PKK-guided PYD as existential threats. Ankara seems unable to shake its phobias about Assad and Syria's western Kurdistan and instead is increasingly identifying with its Sunni instincts, as noted by its growing cooperation with the Saudis.

How do Turkish military experts, who asked not to be identified, assess the complicated current situation?

They say: On one side is a US-supported, anti-Assad, Free Syrian Army pickup truck mounted with a TOW missile. On the other is a US-supported, Russian-made Dushka heavy machine gun mounted on a Kurdish YPG pickup. If the two are engaging each other in combat, this means the defeat of both Turkey and the United States in the field and a victory for Russia.

The YPG is advancing fast and will soon take on IS. When the YPG-IS battles resume, Turkey will not be able to direct artillery fire at the YPG. Then what?