I don't think Putin has a well-defined plan per se. I suspect he's simply testing the waters to see how far he can go without causing any significant blow back.

I don't think Putin has a well-defined plan per se. I suspect he's simply testing the waters to see how far he can go without causing any significant blow back. First he sends some troops in unmarked uniforms to seize the Crimean goverment and parliament buildings. It goes well. He then unofficially moves in some more unmarked troops and equipment and officially requests the Russian parliament to authorize an invasion. He's now probably gauging the reaction of the international community. Also, as history shows, he doesn't necessarily need to seize any territory - installing in situ goverments and establishing secure zones around the borders seemed to have worked to Russia's advantage in Transnestria, Abkhazia, and South Osetia. I don't see why it wouldn't work in Crimea, and - if Putin gets really lucky - in Eastern Ukraine. My only hope is that it doesn't come to a shooting war with mass civilian casualties the way it did in all 3 of those regions. Crimea is a complicated place. The majority of the population are ethnic Russians. But there's a very active Crimean Tatar minority (~15%) which is staunchly pro-Ukrainian (or anti-Russian, if you will). There are also two potentially hostile militaries close to each other - the Ukrainian army has its bases there and Russia keeps its Black Sea Navy units in the Crimean city of Sevastopol.