To argue that the IS carried out the attacks because it has visceral hatred for Western values is to miss the central point. IS has that hatred, but essentially 13/11 was an act of vengeance against France and others who have been bombing the IS.
The air crash might prod the US and its allies to seek a political accommodation with Russia on Syria, and a grand coalition might emerge against the IS. But, even such a coalition will take long to dismantle the IS, assuming it were doable.
The Vienna Conference was far from a gathering of powers with common goals. The key powers involved have yet to reach the conclusion that it is in their interest to end the multiple wars raging in Syria.
It is now abundantly clear that Russia has emerged as the most important player in Syria. With the US on the defensive, the coalition that Russia is forging with Iran and Iraq is likely to get stronger.
There are distressing signals that the EU led by Germany is going in the wrong direction, moving away from the vision of its founders who aspired to build a Europe of democracies based on solidarity among Europeans.
Iran has lent some support to the Houthis, but its support is not a decisive factor. The Saudis have for exaggerated Iran’s role and have in the process made it difficult for themselves to see the reality.