Ukrainian historian Yuriy Korchemniy has never fired an assault rifle in his life, but he joined scores of others and picked up a Kalashnikov when boxes of them were dumped from trucks and handed out to Ukraine’s new volunteer defense units on day two of Russia’s invasion. “They gave out the rifles, loaded them for us and here we are,” the 35-year-old said. The Kyiv bridge underpass he was guarding with a handful of other men — some in their 50s — leads to Western-backed Ukrainian President Volodymyr Zelenskiy’s administrative complex. The reverse side of the road runs through a ...