When I became the supreme military commander at the North Atlantic Treaty Organization in 2009, the alliance was focused on the war in Afghanistan.

But one of the first senior delegations to visit me came to discuss Russia: the military chiefs of Estonia, Latvia and Lithuania.

I’ll never forget the tone in their voices as they described the malevolence of Russian President Vladimir Putin. They had the insiders’ view, as they had ascended through the ranks while their countries were part of the Soviet Union.