ON THE ROAD The air-raid siren sounded again through the defiant city, but William McNulty refused to be bothered by it. After a long morning of meetings in Kyiv with Ukrainian partners in need of medical tourniquets and cold-weather clothing, the man had earned an afternoon nap. The air flowing through the hotel room’s open window nipped of brittle autumn, and sunlight was leaking through gray clouds; winter, as the Ukrainians liked to quip, was coming. F**k it, McNulty thought. The chances of getting hit by a drone strike in a city of three million people seemed low. A U.S....