Affronts to the dignity of a major power by events in a lesser neighbour can have disastrous consequences. Austria was outraged by the assassinations of the archduke and his wife in Sarajevo a century ago. Russia is exceedingly discomfited by what is happening in Ukraine now, with the overthrow of a Russian-leaning regime and its replacement by one looking to the West. Diplomacy failed to avert conflict in 1914; the world cannot allow a similar failure in 2014. The worst case, which is possible but happily not yet probable, is that the unity of the Ukrainian nation will break down in civil war, with Russia supporting one side, Europe and the United States the other. If anything could be worse than Syria, this is it.The two parts of Ukraine are divided by history, language, culture and loy