Many abhor the Assad régime and say that 'something must be done'. This typically means 'by People like Us', Westerners who know how to behave morally - an odd restriction given the only world leader consistently to support the rebels against Assad is Erdogan, the president of Turkey. Western leaders (contrary to the left's 'anti-imperialist' faith) will never do anything against Assad. They don't want to confront Russia and they like Assad's hostility to all Islamists - as do their electorates.
Yet Turkey is officially allied with these Western powers. They incessantly reproach Turkey for not doing enough about ISIS - even though, one would think, the whole Western alliance plus Russia plus the Iraqi Kurds plus Iran and its Iraqi proxies should be able to get the job done without Turkey's help. No matter. Because Turkey opposes America's Syrian proxy, an affiliate of the Kurdish PKK, Erdogan is treated like a naughty boy - a 'difficult ally'. This slant does much to undermine Erdogan's attempt to drag the West, tooth and nail, into putting its money where its mouth is when it comes to deploring Assadist atrocities ( - or at the very least, to stop obstructing aid to the rebels). Western commentators hold against Erdogan his very open anti-PKK campaign, which they disingenuously portray as some dirty secret.
There is no stopping Assad's march of slaughter without giving Turkey freedom to act. The idea that Erdogan is some sort of loose canon stands in the way of this objective. Yet it is not Erdogan who has proven an unreliable, indeed treacherous ally. To appreciate how Turkey has been maligned, you have to look at its reputation and situation.
The West has had many decades of treating Turkey with contempt, at least from the time when, at the outbreak of World War I, the British Royal Navy seized two battleships constructed for the Ottomans and paid for by donations from the Turkish public. A piece by Turkey expert Aaron Stein typifies the condescension with which even the most well-informed analysts view Turkish affairs. It can serve as a point of departure for exploring what's wrong with current views of the US-Turkish alliance.
Here is a passage that gives the flavor of the piece:
...the United States worked for months to assuage Turkish concerns about the military operation to take Manbij from the Islamic State. The ground force, the Syrian Democratic Forces (SDF), is made up primarily of the YPG. The YPG, in turn, rely on air support from a variety of platforms, including drones, A-10s, and allied F-16s based in Turkey. Incirlik was the hub for the planning of the Manbij operation and, eventually, a meeting between Arab, U.S., and Turkish officials to reach a final agreement for the “holding” of the city once ISIL was defeated. The agreement was designed to assuage Turkish concerns about a heavy Kurdish presence west of the Euphrates, something that Turkey had warned was a “red-line” in the past and would prompt military action. Turkey was, without question, difficult to work with during this time, but it ultimately supported the operation and the American-backed plan.
In other words Turkey was reluctant to back an expansion of SDF power; they were "without question, difficult to work with". Stop a moment and consider exactly what this is supposed to mean.
The SDF is nothing but the YPG ("People's Protection Unit"), a Kurdish militia, with some Arabs recruited for cosmetic purposes. The YPG is an arm of the PKK ("Kurdistan Workers' Party"), a fact only the PKK occasionally and feebly denies, also for cosmetic purposes. The PKK and Turkey have been at war for decades.
This is not a small war. It involves hundreds of casualties on both side and extensive use for heavy weapons. It is accompanied by terrorist attacks in which many civilians die. Most recently, the PKK broke a truce and killed three Turkish policemen. The stated reason for this act wasn't any of Turkey's attacks on the Kurdish people. It was because the Islamic State had blown up a gathering of young PKK supporters on Turkish soil.
Turkey can't make decisive progress against the PKK because it has sanctuary in Northern Syria. There the PKK has an alliance of convenience with the Assad régime, also an enemy of Turkey. The US has adopted the YPG, the PKK's Syrian affiliate, as a proxy against the Islamic State. The US and its 'coalition' have provided the PKK with huge quantities of weapons and millions of dollars. They have also provided extensive close air support for PKK operations. This of course has strengthened the PKK immeasurably, and emboldened them. Reports refer to "the Kurds’ ambitions, which have been fueled by the support they have received from the U.S military."
Via its SDF militia, the PKK has attacked Turkish-backed anti-Assad forces. In so doing it has crossed the Euphrates from east to west. This is what Turkey termed a red line, because PKK expansion in that direction promised to give the PKK control over extensive, crucial stretches of the Syrian-Turkish border. Of course that would facilitate PKK actions against Turkey immensely. The US agreed not to let this happen and then did nothing to enforce its agreement.
Because the geography is so different, it is hard to construct a comparison which helps decide whether Turkey is being 'difficult'. But here's a very imperfect attempt.
Suppose Al Qaeda had established itself in central Canada and conducted intermittently successful military actions in the American Midwest. It then gained some territory on the New York-Canada border. The EU, having found Al Qaeda useful for its own purposes, was pouring arms and money into the AQ forces using, incredibly, bases in Boston to do so. It gained access to these bases by promising not to let AQ into New York state. AQ, however, did deploy in upper New York state, and the EU did nothing about it. Having lost thousands in the fight against AQ, the US was kinda upset. Did that make the US a difficult ally?
The example is absurd because the story can't get started. A US government that granted the EU bases for supplying Al Qaeda operations inside the US wouldn't last for a second. So there's no puzzle about Turkish reaction to US policy except why it was so mild in the first place. Turkey might quite reasonably have withdrawn its ambassador to Washington at the first suggestion that 'The Coalition' should have anything to do with the Kurds. So here's what's really hard to understand: how analysts and news media can muster enough obliviousness not to marvel at the abuse to which Turkey is subjected in virtually all discussions of the US/EU/NATO alliance.
None of this is to deny that or discuss whether the PKK, much less the Kurds, had excellent reason for every single action they ever mounted against Turkey and Turks. Maybe they did. The issue is whether Turkey was a difficult ally. That turns not on whether Turkey acts with moral justification but on whether the US treats Turkey as allies normally do. The US does nothing of the sort.