(This post has been corrected and combined with two other posts, to create the more complete Ukraine: The Great Game, v2.0. I am leaving it here so that links and references stand.)
I spent an hour online last night, discussing the geopolitics with a German-American, who is all for US intervention. She has a point: we don't want Russian imperialism—and it probably is that—to go unchecked. Juan Cole points out that Turkey is surrounded by Ukraine, Syria, and Iran. After reading that, and thinking some more about it, I spent time looking at the Google Earth globe and imagining a giant Go board, stretching from the Ukraine to Indonesia.
I think we are back in the multipolar world, where great powers dream of empire and radicals dream of global federalism. I don't think we get to withdraw from the game without dire consequences. And climate change is the game timer.