Igor Salikov knows his life is in danger. That’s the risk the Russian officer took when he disobeyed orders in Ukraine and defected to the West. But having witnessed the depravity of Vladimir Putin’s military, including the notorious Wagner mercenary group, he feels compelled to reveal its secrets. On 20 February, 2022, news came through that Russia would be invading Ukraine in four days’ time. Salikov, who had spent decades in Moscow’s armed forces while rising to the rank of major, was shocked. As a senior officer in a commando division of the GRU, one of Putin’s intelligence agencies, he...