I won't even pretend to fully understand the complexity of the Russia-Ukraine situation, but I found it interesting to read Putin's entire speech. Like most things in Russia seem to be, it's steeped in historical context...or at least one man's perspective of it.
It's a long one, and bring a bag of salt, but if you have 10 minutes...always neat to read a primary source.
http://en.kremlin.ru/events/president/transcripts/67828