Syria, Islamic State, and seeing conspiracies that weren't there.
This is especially true when it comes to Syria in terms of oil. Practically, everyone is guilty of buying and selling to each other: Islamic State sold to Assad. Islamic State sold to Turkey. Thieves stole from Islamic State and sold to everyone. Trying to make some grand statement about how about one country or one side is in bed with another on the basis of oil is foolish. Turkey until recently turned a blind eye to Islamic State and other foreign fighters travelling through her borders as they didn't care who replaced Assad, as long as he fell. Of all the double games that have been played, Turkey's has been just about the most egregious.
And yet, even now, even after the retaking of Palmyra by the Syrian Arab Army, still this kind of nonsense is being spouted, including by the Graun:
The second conclusion is that when governments stop playing a double game in which they use extremists for their own purposes, they do better. Assad did this for a long time, leaving Isis alone so as to put more pressure on its other opponents. After the loss of Palmyra in May 2015, the Syrians abandoned that policy and tried to retake the areas they had lost, but they had not the resources and, in particular, the airpower to do so, until the Russians made up that deficiency.
To an extent, Assad did indeed leave Islamic State alone. This was for the reason that the territory taken by IS in the country's eastern, mostly desert regions was not strategically essential to the regime's survival. The SAA gave up Palmyra in order to retrench and reinforce its other frontlines, primarily around Damascus, Latakia, and in Aleppo. It was only after the Russian intervention at the end of September last year that the SAA alongside Hezbollah and other groups was finally able to make some headway, and then it took months. Likewise, Islamic State has somewhat learned the lesson of the thrashing it received in Kobane, once the Americans decided the overrunning of the town would be an advance too far; they withdrew from Palmyra to cut their losses, as they also did in Sinjar in Iraq.
As Juan Cole writes, it's not immediately clear why the SAA would now retake Palmyra when the likes of al-Nusra are still much closer to home. Part of the reasoning is no doubt for symbolic reasons, that expelling IS from Palmyra makes for good propaganda. Whatever the exact motives, it does dispel once and for all the idiotic notion that there was some kind of accord between Assad and IS, or that the Russians were effectively Islamic State's air force, or any such gibbering. The retaking of Palmyra has happened primarily because of the ceasefire with the groups other than IS and al-Nusra, which is holding to the surprise of pretty much everyone; without wanting to blow my own trumpet too loud, this is what I suggested was the more realistic outcome if a ceasefire happened. Not the "70,000 moderates" fighting Islamic State for us, but the SAA backed by the Russians from the air.
Whether retaking Palmyra is purely symbolic, with the Russians having no intention of providing the backup required for the SAA and allies to retake Raqqa, the ultimate target once Deir al-Zor has been relieved, we're yet to see. We don't for instance know if like in Palmyra Islamic State might simply retreat; the declared capital of their caliphate or not, Mosul seems more likely to be where IS would choose to make a last stand.
Last stand is in any case a relative notion. Just as IS's previous incarnation, the Islamic State of Iraq, appeared to have been defeated, Islamic State seems unlikely to be defeated completely when its resurrection was far more an expression of the rage of Iraq's Sunnis at their on-going persecution and under-representation in post-war Iraq than it was sudden support for the group's internationalist ideology. Also unlike in Syria, where those who have survived have been hardened and bloodied by the experience, in Iraq the army still seems to have fundamental issues with morale, continuing to run away at the first sign of Islamic State striking back. Retaking Mosul remains an ideal, not something likely to turn into actuality any time soon.
As for whether or not you believe the reports about "hundreds" of foreign fighters being sent back to attack Europe, that the cell that first attacked Paris and then Brussels seems to be as large as it was hardly suggests a lack of ambition. Even if IS loses the territory it holds, its success has been in updating the template laid down by al-Qaida, creating a banner to which both the disaffected and the deeply religious have been attracted. Either it will rise again, or another group, even less scrupulous, even more murderous will take its place. What will really matter is if we then repeat the same mistakes we have twice already. I'm not betting on the third time being the charm.