Apparently on the news (I don't have a link, was mentioned in conversation with my mum) it was stated the UN has declared Russia's actions as an act of war.
Whilst I agree it would be best to let it end without any loss of life, the problem isn't necessarily national pride, it's giving in to what could be called bullying (or rather terrorism) to an extent - "Give us this or we'll beat you up". Which if they cave, sends a signal to everyone else, but even just regarding Russia where does it end. I would hope that Crimea is all they want, but he may turn out to be more greedy and start wondering what else he can get out of it. That is of course, a worst case scenario and I hope it would never come to anything even like that.
Aren't they trying to declare this as "protecting our citizens"? I was under the impression that the issues in Kiev were a) in Kiev and b) over. Further more if they are living in Crimea then they are surely not Russia's responsibility to protect any more... I mean if something kicked off in Britain I wouldn't expect a large deployment of Polish troops to suddenly appear to protect the Polish living here. This is after all what the Police and Military of the country are for, to protect people living there, not just people who were born there.