With regard to eastern Ukraine, particularly after the results of the Crimean referendum and the people voting to join Russia, the ethnic Russian speaking people may very well push for their own referendum to leave Ukraine and join Russia.
For his part Putin is unlikely to send troops into eastern Ukraine unless the ethnic Russians are threatened and brutalized by the Ukrainian authorities- which he rightly believes is unlawful, un-elected and there only because of the U.S. provoked coup that brought them to power.
As for the U.S. and the E.U. the latest has them placing sanctions on some 21 Russian and Ukrainian political figures, which apparently was met with derision and mockery in Moscow with one of them saying, "This is a big honor for me".
However if hard sanctions by the U.S. and the E.U. are applied on Russia it will only provoke Russia to counter with its own actions which likely would include restricting the flow of natural gas it supplies to Europe, particularly Germany, the economic powerhouse in the E.U.
At this point with events happening rapidly its hard to know what tit for tat "games" are in store and what further developments may be happening on the ground in Ukraine.
Eventually, the threats and bombast will subside and real diplomacy will come to the fore.
Just consider; all Europe knows war first hand from the two world wars; so do the Russians who suffered some 20 million casualties in the last world war.
Only the continental U.S. and its population were spared with no domestic losses and no infrastructure damage from the war.
Now unless the U.S. government has completely lost its sanity it won't provoke and push Putin and Russia into a corner.
World War I was a monumental horror. W.W. II happened as a direct result of W.W.I The world won't survive a nuclear W.W.III.
[i] "The Looting of Ukraine Has Begun", Paul Craig Roberts, OPEDNEWS, March 6, 2014
[ii] "Ultimately, The Breakup and Partition of Ukraine May Be The Only Viable Solution to Ending the Crisis", Dave Lefcourt, OPEDNEWS, March 3, 2014.
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