Lots of people seeing 'wood', very few seeing 'trees'.
Energy is the mainstay of the Russian economy - and without the revenues from the oil and gas, they will be queuing for potatoes again pretty quick.
Oil prices below $117 a barrel start to interfere with the Russian economy and below $60 a barrel Putin is effectively toast [no standing back for a caretaker president for a few years in this case].
As an aside, Russia has a good energy deal going with Syria - exchanging Syrian crude for refined Russian petrochemicals at a favourable rate..... still I am sure that's completely unconnected to the veto against action on Syria.
Not only is he humiliating a politically and militarily impotent West, but causing a spike in oil prices. The last thing he wants is a war - but a prolonged stand off and heightened tensions suit his purposes perfectly.
The best course of action would be to let him have Eastern Ukraine and the Crimea; the majority want to be Russian anyway. Take away his oxygen and let the oil price flatline is far more damaging to Russia than sanctions or hollow threats.