Yeah, we (the U.S.) kind of lost our footing on the moral high ground when we invaded Iraq. Now it's pretty hard to keep a straight face when chastising another country for doing exactly what we have done in the recent past.
It only matters because it is Europe. And it is our old nemesis of Russia (still wearing the tattered cloak of the USSR)
Putin knows that the UN lacks any real motivation to do anything but talk. Putin has a lot of support in Russia, probably a fair amount of support in the Ukraine as well. He is ex-KGB, an old dog of the Soviet system; he knows how to spin, what to say to keep everyone just a little off balance.
We will go through the motions of opposing the move, talk tough, maybe impose sanctions, trade rhetoric, and keep up appearances until it blows over or the American public losses interest and moves on to the next news story.
Republicans will take whatever stance opposes the president. Democrats will fall in line with the administration...
Same as it ever was, same as it ever was...