PETRO POROSHENKO, the front-runner in Ukraine’s presidential election, due on May 25th, exudes confidence. “There is no uncertainty. Ukraine will have free and fair elections and a strong legitimate president who will bring it closer to Europe. No Russian troops will cross the border.” His words are like psychotherapy. After a revolutionary winter, the overthrow of a president, Viktor Yanukovych, and the annexation of Crimea by Russia, Ukrainians feel fragile and exhausted. They crave respite, peace and normal life. Instead, they are getting provocations, threats of invasion and gas-price rises, and Russian-fuelled separatism. All this is part of what is known as the “Russian spring”. The activity of Russian agents in eastern Ukraine had seemed to be subsiding; separatist rallies were abating. But on April 6th the Russian spring returned spectacularly.In a carefully co-ordinated action, groups of men, some armed, took over government buildings in Donetsk, Luhansk and Kharkiv, declared the “independence” of eastern Ukrainian republics, demanded referendums and called for Russian assistance. They aped the Maidan protesters in Kiev with barricades made of car tyres…