This is a great video on the Russian perspective and strategy towards Eastern Europe.  The Russian incursion into Crimea and eastern Ukraine is without a doubt the most dangerous situation to cross the desk of the President Barack Obama since his election.  Skillful management could ease tensions and establish meaningful boundaries that allow both sides to resume normal relations.  Mismanagement can easily result in armed conflict on a scale not seen in decades.  So far the administration has been measured and gradual in its escalation of rhetoric and sanctions.  Time will tell.