Russian President Vladimir Putin and Defence Minister Sergei Shoigu speak after a military parade on Victory Day, marking the 77th anniversary of the victory over Nazi Germany in World War Two, in Red Square in central Moscow, on May 9.MAXIM SHEMETOV/Reuters His army has made three humiliating retreats in Ukraine in the past year and nearly 200,000 of his men have been killed or wounded according to U.S. officials, but Russia’s defence minister is still in a job thanks to President Vladimir Putin. The Russian leader has various reasons for keeping Sergei Shoigu, 67, in post, according to Western officials,...