David Petraeus is a former CIA director who, as a four-star general, led US military campaigns in Iraq and Afghanistan. He speaks to the historian Niall Ferguson about the war in Ukraine. NIALL FERGUSON: General, I wanted to ask you to give your assessments of the Russian invasion of Ukraine. If you were grading Russia’s military performance and Ukraine’s, what grades would you give? DAVID PETRAEUS: Clearly Russia has failed. That’s the only way to describe the campaign thus far. And the Ukrainians, gosh, I think you have to give them an A at least and perhaps even more for just the sheer determination. But it’s much more than fighting for their very survival. They have done it very, very impressively. The entire nation has been galvanised by a leader who has been positively Churchillian.