Russian president Vladimir Putin is "a very dangerous beast," says preeminent military historian Antony Beevor. As war rages in Ukraine, an unpredictable dictator may risk expanding the war to involve NATO members such as the Baltic states. Putin has fallen into the same trap as past Russian and Soviet leaders, obsessed with a perceived encirclement by implacable, hostile powers to the west. In this episode, Sir Antony Beevor explains the deep historical roots of the conflict in Eastern Europe, and the ways in which Putin is trying to turn back the clock to an imperial past.