HeadClot: I fear for the worst.
vsr: I think it is inevitable. Russia is the largest and only country which stands in the way of USA. And has a lot of resources USA and Europe need.
USA is constantly destabilizing borders of Russia and eventually this will grow into full fledged war.
War will feed USA, like it did during WWII.
A lot of europeans and russians will die, but americans will prosper (if USA will not be nuked).
That's why it is essential to NATO to disarm russian nuclear forces by placing in Ukraine AEGIS missiles, which will intercept russian missiles early on, effectively negating nuclear strike back on USA. Crimea was lost and it is a great strategic failure for NATO countries, but future is still uncertain.
Worry not, american. Europeans should fear - theirs role is cannon fodder in future War.
Hypothetically... I think both sides will collapse economically before we reach full-fledged war, and Russia, having an economy which is a fraction of the size of either the EU or the US, and which depends much more on exports to Europe and the US than vice versa -- and more specifically on energy prices staying at the unusual heights of the last ~decade -- would be likely to collapse first.
Indeed, the interdependence of the post-cold war global economy, adding to the nuclear MAD of the cold war, makes anything beyond low-level proxy warfare practically suicidal (whether that's e.g. Russia invading the Baltics or NATO directly intervening in East Ukraine). Also: "only country which stands in the way of USA." -- China says hi. China, the massive export economy of which is so dependent on Western markets that they have invested astronomic amounts in the last decades propping up those markets. I'm sure they'd appreciate cheap(er) Russian energy as a result of further deterioration of the Russian-Western relationship, but if Western demand for goods were to lessen/disappear they would require less rather than more energy.