War seems so far fetched, it's possible, but highly unlikely. Technology has advanced too much that a war between the west and Russia, isn't the best idea in the world. Both will lose a lot in the event that it happens, while war is absolutely about losing and no winning economy-wise, no country will get out of it unscathed or with little damage, so no, I don't think they'll do it.
All they can do is put in more sanctions if they can, but then Russia, as stated is more interested in Asia than in the western countries. Therefore giving sanctions is like throwing pebbles at them, they don't care and it doesn't affect Putin as much as they think it does.