Russia, France, Germany, and Ukraine held Normandy peace talks back in January, some of the things the Russians asked for (paraphrased): Russian-speaking regions of Donetsk and Luhansk would be granted special status within Ukraine, security guarantees from NATO, a limitation of the number of troops stationed in Eastern Ukraine, and Ukraine restoring the fresh water supply that they cut off from Crimea. Conceding on some of those things might have been a good alternative to war.