If the Russians don't obey the West, and dare to support the Syrian Army in liberating the Syrian oilfields in the East, the Western Intelligence Services will make sure the Russians lose another airliner filled with civilians. They already lost one in Egypt when started their intervention a couple of years ago in Syria, and they recently lost another one in Russia.
I'm pretty sure MH-17 was their work too, to send a message to Russia as well as to Malaysia. But I don't think the Russians are planning to back off, after hearing Putin's latest speech.