Rush Limbaugh could be POTUS, Sarah Palin could be in charge of the State Department, Ted Nugent could be SecDef and the US military could be three times bigger and Putin would STILL have annexed Crimea and there would be still nothing the US could or would want to do about it.
Russia holds all the cards here. We're looking at the 1930s with nuclear deterrence thrown into the mix.
This is all about Putin's power and his continued grip on his country. He has no concerns about what we in the west think. Western leaders can boycott the G8 and the Paralympics all they want. The guy's a sociopath in charge of a nuclear arsenal, strategic forces and a whole bunch of natural gas and it won't matter to him what they do or do not do.
Whatever your political leanings, at this stage the best we can hope for is that he stops short of invading the rest of the Ukraine, that the Ukrainians themselves see sense and give up Crimea without attempting a fight, and that he doesn't go truly off the reservation and start looking at somewhere like the Baltic states next.
I know this reeks of appeasement and I know we're supposed to learn from history, but noone in their right mind is going to send the 6th Fleet to the Black Sea. I hope.