With the continual cry for freedom from corrupt and oppressive governments resulting in uprisings all over the world, the situation for Russia over it's incursion into Ukrainian sovereignty is very risky for Putin. Russia may be able to bark at the west concerning Syria and the Middle-East crisis, but stirring up a Russian Spring " over armed conflict in Ukraine is likely, and another matter altogether.
While Russia has been re-building it's military and infrastructure for years, they still do not have the hearts and minds of their own people in sync with their oliarchist nationalistic political machine. Most Russians can plainly see other nations taking control of their destinies through popular insurrections in protests and civil disobedience bringing down the systems of failed policies, demanding freedom from elitism and blatant nepotism and cronyism that has poisoned government for the people. They can taste a Springtime also.
Russia may have it's own civil unrest problems if it's populace is polarized by intervention and military involvement that brings sanctions and embargo to an already fragile economy. Oil and gas exports continue to be the main source of hard currency. Russia has the largest reserves, and is the largest exporter, of natural gas. It has the second largest coal reserves, the eighth largest oil reserves, and is the largest exporter of oil in the world. If the European Union who stops buying their oil and natural gas as punishment, Russia will immediately feel the crunch as the EU comprises 60% of their customer base. Russia could not sustain appearing a credible deterrent against arming Syrian Rebel forces in that conflict and and perhaps encouraging Israel to make it's move at a strategic strike on Iranian Nuclear facilities while Russia is embroiled in too much of it's own internal turmoil.
Russia and The EU would be very close to setting off a conflict that could spark very ugly results. In this volatile world and destabilized economy, it's anybody's guess how short the fuse would have to be to inflame the world in catastrophic military conflict.
The United States could become polarized as well because of the divisiveness in our political climate over any intervention on our part. With polls rising for presidential candidates like Rand Paul who would take an isolationist position, and may very well get elected because the U.S.gets drawn into the Russian-Ukraine-EU mess by our NATO treaties, The U.S. could very well taste an American Spring upheaval herself.