It would be very foolish for the Russians to start shooting. The population of the Crimea supports them and time is on their side. The West is powerless to intervene despite the paranoid fantasies of Russian military commanders.
Perhaps the Crimea is just a pretext for something more?
Agreed. Russia has Crimea. The Ukrainian forces there pose no threat.
Putin knows his own country's politics. Time may be on the side of the Crimea, but Putin won't hesitate to do what he has to, NO MATTER WHAT. HE believes that what he is doing NOW is in the best interests of Russia.
I don't believe that we, here in the West, get the whole story from our media. To me, they are spineless scum who sell their souls to be near Hollywood. So who HERE really knows the whole story? NO ONE.
Oops, do I sound HARSH here?
Yes, but Putin doesn't just want to get Crimea (or Ukraine). He also wants to demonstrate to the world (and especially the Middle East) that the United States is becoming a yapping irrelevancy and that the big dog, to whom they should now pay attention and look to for leadership, is Russia. Putin's Russia. A little "shoot-em up" actually advances Putin's strategy. He wants a war, or at least, a small one.
A military assault on Ukrainian forces in Crimea would show the world (and particularly the US) that Russia is serious about the whole affair and is willing to shed their blood for it.
After that, there will be no going back to previous borders.
Full scale war with Ukraine (if not all of NATO) is still a possibility, and it is a bad idea to leave pockets of surrounded but armed enemy troops behind your lines.